Subject: Re: [RFC PATCH 1/2] Add C TAP harness

From: Phillip Wood <[email-masked]>
Date: Thu, 27 Apr 2023 21:15:18 +0100

Hi Calvin

On 27/04/2023 18:50, Calvin Wan wrote:
> Introduces the C TAP harness from https://github.com/rra/c-tap-harness/
> 
> There is also more complete documentation at
> https://www.eyrie.org/~eagle/software/c-tap-harness/

I'm afraid this reply is rather briefer than I'd like but I'm short of 
time and about to go off-list for a couple of weeks. My ideal unit test 
library would

  - print the file and line number of failed assertions
  - allow the test plan to be omitted by calling test_done() at the end
    of the test file as we do in our main test suite.
  - support the TODO directive
  - allow named tests (this maybe more trouble that it is worth as I
    think it inevitably leads to more boilerplate code calling the named
    tests)

Unfortunately this library doesn't seem to offer any of those features. 
It does support a lazy test plan but uses atexit() so will not detect if 
the test program exits before all the tests have run. I think it would 
be useful to add some unit tests to our test suite and maybe this 
library could form the basis of that but I think printing the file and 
line number of failed assertions is pretty essential.

Best Wishes

Phillip

> Signed-off-by: Calvin Wan <[email-masked]>
> ---
>   t/TESTS        |    0
>   t/runtests.c   | 1789 ++++++++++++++++++++++++++++++++++++++++++++++++
>   t/tap/basic.c  | 1029 ++++++++++++++++++++++++++++
>   t/tap/basic.h  |  198 ++++++
>   t/tap/macros.h |  109 +++
>   5 files changed, 3125 insertions(+)
>   create mode 100644 t/TESTS
>   create mode 100644 t/runtests.c
>   create mode 100644 t/tap/basic.c
>   create mode 100644 t/tap/basic.h
>   create mode 100644 t/tap/macros.h
> 
> diff --git a/t/TESTS b/t/TESTS
> new file mode 100644
> index 0000000000..e69de29bb2
> diff --git a/t/runtests.c b/t/runtests.c
> new file mode 100644
> index 0000000000..4a55a801a6
> --- /dev/null
> +++ b/t/runtests.c
> @@ -0,0 +1,1789 @@
> +/*
> + * Run a set of tests, reporting results.
> + *
> + * Test suite driver that runs a set of tests implementing a subset of the
> + * Test Anything Protocol (TAP) and reports the results.
> + *
> + * Any bug reports, bug fixes, and improvements are very much welcome and
> + * should be sent to the e-mail address below.  This program is part of C TAP
> + * Harness <https://www.eyrie.org/~eagle/software/c-tap-harness/>.
> + *
> + * Copyright 2000-2001, 2004, 2006-2019, 2022 Russ Allbery <[email-masked]>
> + *
> + * Permission is hereby granted, free of charge, to any person obtaining a
> + * copy of this software and associated documentation files (the "Software"),
> + * to deal in the Software without restriction, including without limitation
> + * the rights to use, copy, modify, merge, publish, distribute, sublicense,
> + * and/or sell copies of the Software, and to permit persons to whom the
> + * Software is furnished to do so, subject to the following conditions:
> + *
> + * The above copyright notice and this permission notice shall be included in
> + * all copies or substantial portions of the Software.
> + *
> + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
> + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
> + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
> + * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
> + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
> + * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
> + * DEALINGS IN THE SOFTWARE.
> + *
> + * SPDX-License-Identifier: MIT
> + */
> +
> +/*
> + * Usage:
> + *
> + *      runtests [-hv] [-b <build-dir>] [-s <source-dir>] -l <test-list>
> + *      runtests [-hv] [-b <build-dir>] [-s <source-dir>] <test> [<test> ...]
> + *      runtests -o [-h] [-b <build-dir>] [-s <source-dir>] <test>
> + *
> + * In the first case, expects a list of executables located in the given file,
> + * one line per executable, possibly followed by a space-separated list of
> + * options.  For each one, runs it as part of a test suite, reporting results.
> + * In the second case, use the same infrastructure, but run only the tests
> + * listed on the command line.
> + *
> + * Test output should start with a line containing the number of tests
> + * (numbered from 1 to this number), optionally preceded by "1..", although
> + * that line may be given anywhere in the output.  Each additional line should
> + * be in the following format:
> + *
> + *      ok <number>
> + *      not ok <number>
> + *      ok <number> # skip
> + *      not ok <number> # todo
> + *
> + * where <number> is the number of the test.  An optional comment is permitted
> + * after the number if preceded by whitespace.  ok indicates success, not ok
> + * indicates failure.  "# skip" and "# todo" are a special cases of a comment,
> + * and must start with exactly that formatting.  They indicate the test was
> + * skipped for some reason (maybe because it doesn't apply to this platform)
> + * or is testing something known to currently fail.  The text following either
> + * "# skip" or "# todo" and whitespace is the reason.
> + *
> + * As a special case, the first line of the output may be in the form:
> + *
> + *      1..0 # skip some reason
> + *
> + * which indicates that this entire test case should be skipped and gives a
> + * reason.
> + *
> + * Any other lines are ignored, although for compliance with the TAP protocol
> + * all lines other than the ones in the above format should be sent to
> + * standard error rather than standard output and start with #.
> + *
> + * This is a subset of TAP as documented in Test::Harness::TAP or
> + * TAP::Parser::Grammar, which comes with Perl.
> + *
> + * If the -o option is given, instead run a single test and display all of its
> + * output.  This is intended for use with failing tests so that the person
> + * running the test suite can get more details about what failed.
> + *
> + * If built with the C preprocessor symbols C_TAP_SOURCE and C_TAP_BUILD
> + * defined, C TAP Harness will export those values in the environment so that
> + * tests can find the source and build directory and will look for tests under
> + * both directories.  These paths can also be set with the -b and -s
> + * command-line options, which will override anything set at build time.
> + *
> + * If the -v option is given, or the C_TAP_VERBOSE environment variable is set,
> + * display the full output of each test as it runs rather than showing a
> + * summary of the results of each test.
> + */
> +
> +/* Required for fdopen(), getopt(), and putenv(). */
> +#if defined(__STRICT_ANSI__) || defined(PEDANTIC)
> +#    ifndef _XOPEN_SOURCE
> +#        define _XOPEN_SOURCE 500
> +#    endif
> +#endif
> +
> +#include <ctype.h>
> +#include <errno.h>
> +#include <fcntl.h>
> +#include <limits.h>
> +#include <stdarg.h>
> +#include <stddef.h>
> +#include <stdio.h>
> +#include <stdlib.h>
> +#include <string.h>
> +#include <strings.h>
> +#include <sys/stat.h>
> +#include <sys/time.h>
> +#include <sys/types.h>
> +#include <sys/wait.h>
> +#include <time.h>
> +#include <unistd.h>
> +
> +/* sys/time.h must be included before sys/resource.h on some platforms. */
> +#include <sys/resource.h>
> +
> +/* AIX 6.1 (and possibly later) doesn't have WCOREDUMP. */
> +#ifndef WCOREDUMP
> +#    define WCOREDUMP(status) ((unsigned) (status) &0x80)
> +#endif
> +
> +/*
> + * POSIX requires that these be defined in <unistd.h>, but they're not always
> + * available.  If one of them has been defined, all the rest almost certainly
> + * have.
> + */
> +#ifndef STDIN_FILENO
> +#    define STDIN_FILENO  0
> +#    define STDOUT_FILENO 1
> +#    define STDERR_FILENO 2
> +#endif
> +
> +/*
> + * Used for iterating through arrays.  Returns the number of elements in the
> + * array (useful for a < upper bound in a for loop).
> + */
> +#define ARRAY_SIZE(array) (sizeof(array) / sizeof((array)[0]))
> +
> +/*
> + * The source and build versions of the tests directory.  This is used to set
> + * the C_TAP_SOURCE and C_TAP_BUILD environment variables (and the SOURCE and
> + * BUILD environment variables set for backward compatibility) and find test
> + * programs, if set.  Normally, this should be set as part of the build
> + * process to the test subdirectories of $(abs_top_srcdir) and
> + * $(abs_top_builddir) respectively.
> + */
> +#ifndef C_TAP_SOURCE
> +#    define C_TAP_SOURCE NULL
> +#endif
> +#ifndef C_TAP_BUILD
> +#    define C_TAP_BUILD NULL
> +#endif
> +
> +/* Test status codes. */
> +enum test_status {
> +    TEST_FAIL,
> +    TEST_PASS,
> +    TEST_SKIP,
> +    TEST_INVALID
> +};
> +
> +/* Really, just a boolean, but this is more self-documenting. */
> +enum test_verbose {
> +    CONCISE = 0,
> +    VERBOSE = 1
> +};
> +
> +/* Indicates the state of our plan. */
> +enum plan_status {
> +    PLAN_INIT,    /* Nothing seen yet. */
> +    PLAN_FIRST,   /* Plan seen before any tests. */
> +    PLAN_PENDING, /* Test seen and no plan yet. */
> +    PLAN_FINAL    /* Plan seen after some tests. */
> +};
> +
> +/* Error exit statuses for test processes. */
> +#define CHILDERR_DUP    100 /* Couldn't redirect stderr or stdout. */
> +#define CHILDERR_EXEC   101 /* Couldn't exec child process. */
> +#define CHILDERR_STDIN  102 /* Couldn't open stdin file. */
> +#define CHILDERR_STDERR 103 /* Couldn't open stderr file. */
> +
> +/* Structure to hold data for a set of tests. */
> +struct testset {
> +    char *file;                /* The file name of the test. */
> +    char **command;            /* The argv vector to run the command. */
> +    enum plan_status plan;     /* The status of our plan. */
> +    unsigned long count;       /* Expected count of tests. */
> +    unsigned long current;     /* The last seen test number. */
> +    unsigned int length;       /* The length of the last status message. */
> +    unsigned long passed;      /* Count of passing tests. */
> +    unsigned long failed;      /* Count of failing lists. */
> +    unsigned long skipped;     /* Count of skipped tests (passed). */
> +    unsigned long allocated;   /* The size of the results table. */
> +    enum test_status *results; /* Table of results by test number. */
> +    unsigned int aborted;      /* Whether the set was aborted. */
> +    unsigned int reported;     /* Whether the results were reported. */
> +    int status;                /* The exit status of the test. */
> +    unsigned int all_skipped;  /* Whether all tests were skipped. */
> +    char *reason;              /* Why all tests were skipped. */
> +};
> +
> +/* Structure to hold a linked list of test sets. */
> +struct testlist {
> +    struct testset *ts;
> +    struct testlist *next;
> +};
> +
> +/*
> + * Usage message.  Should be used as a printf format with four arguments: the
> + * path to runtests, given three times, and the usage_description.  This is
> + * split into variables to satisfy the pedantic ISO C90 limit on strings.
> + */
> +static const char usage_message[] = "\
> +Usage: %s [-hv] [-b <build-dir>] [-s <source-dir>] <test> ...\n\
> +       %s [-hv] [-b <build-dir>] [-s <source-dir>] -l <test-list>\n\
> +       %s -o [-h] [-b <build-dir>] [-s <source-dir>] <test>\n\
> +\n\
> +Options:\n\
> +    -b <build-dir>      Set the build directory to <build-dir>\n\
> +%s";
> +static const char usage_extra[] = "\
> +    -l <list>           Take the list of tests to run from <test-list>\n\
> +    -o                  Run a single test rather than a list of tests\n\
> +    -s <source-dir>     Set the source directory to <source-dir>\n\
> +    -v                  Show the full output of each test\n\
> +\n\
> +runtests normally runs each test listed on the command line.  With the -l\n\
> +option, it instead runs every test listed in a file.  With the -o option,\n\
> +it instead runs a single test and shows its complete output.\n";
> +
> +/*
> + * Header used for test output.  %s is replaced by the file name of the list
> + * of tests.
> + */
> +static const char banner[] = "\n\
> +Running all tests listed in %s.  If any tests fail, run the failing\n\
> +test program with runtests -o to see more details.\n\n";
> +
> +/* Header for reports of failed tests. */
> +static const char header[] = "\n\
> +Failed Set                 Fail/Total (%) Skip Stat  Failing Tests\n\
> +-------------------------- -------------- ---- ----  ------------------------";
> +
> +/* Include the file name and line number in malloc failures. */
> +#define xcalloc(n, type) \
> +    ((type *) x_calloc((n), sizeof(type), __FILE__, __LINE__))
> +#define xmalloc(size)     ((char *) x_malloc((size), __FILE__, __LINE__))
> +#define xstrdup(p)        x_strdup((p), __FILE__, __LINE__)
> +#define xstrndup(p, size) x_strndup((p), (size), __FILE__, __LINE__)
> +#define xreallocarray(p, n, type) \
> +    ((type *) x_reallocarray((p), (n), sizeof(type), __FILE__, __LINE__))
> +
> +/*
> + * __attribute__ is available in gcc 2.5 and later, but only with gcc 2.7
> + * could you use the __format__ form of the attributes, which is what we use
> + * (to avoid confusion with other macros).
> + */
> +#ifndef __attribute__
> +#    if __GNUC__ < 2 || (__GNUC__ == 2 && __GNUC_MINOR__ < 7)
> +#        define __attribute__(spec) /* empty */
> +#    endif
> +#endif
> +
> +/*
> + * We use __alloc_size__, but it was only available in fairly recent versions
> + * of GCC.  Suppress warnings about the unknown attribute if GCC is too old.
> + * We know that we're GCC at this point, so we can use the GCC variadic macro
> + * extension, which will still work with versions of GCC too old to have C99
> + * variadic macro support.
> + */
> +#if !defined(__attribute__) && !defined(__alloc_size__)
> +#    if defined(__GNUC__) && !defined(__clang__)
> +#        if __GNUC__ < 4 || (__GNUC__ == 4 && __GNUC_MINOR__ < 3)
> +#            define __alloc_size__(spec, args...) /* empty */
> +#        endif
> +#    endif
> +#endif
> +
> +/*
> + * Suppress the argument to __malloc__ in Clang (not supported in at least
> + * version 13) and GCC versions prior to 11.
> + */
> +#if !defined(__attribute__) && !defined(__malloc__)
> +#    if defined(__clang__) || __GNUC__ < 11
> +#        define __malloc__(dalloc) __malloc__
> +#    endif
> +#endif
> +
> +/*
> + * LLVM and Clang pretend to be GCC but don't support all of the __attribute__
> + * settings that GCC does.  For them, suppress warnings about unknown
> + * attributes on declarations.  This unfortunately will affect the entire
> + * compilation context, but there's no push and pop available.
> + */
> +#if !defined(__attribute__) && (defined(__llvm__) || defined(__clang__))
> +#    pragma GCC diagnostic ignored "-Wattributes"
> +#endif
> +
> +/* Declare internal functions that benefit from compiler attributes. */
> +static void die(const char *, ...)
> +    __attribute__((__nonnull__, __noreturn__, __format__(printf, 1, 2)));
> +static void sysdie(const char *, ...)
> +    __attribute__((__nonnull__, __noreturn__, __format__(printf, 1, 2)));
> +static void *x_calloc(size_t, size_t, const char *, int)
> +    __attribute__((__alloc_size__(1, 2), __malloc__(free), __nonnull__));
> +static void *x_malloc(size_t, const char *, int)
> +    __attribute__((__alloc_size__(1), __malloc__(free), __nonnull__));
> +static void *x_reallocarray(void *, size_t, size_t, const char *, int)
> +    __attribute__((__alloc_size__(2, 3), __malloc__(free), __nonnull__(4)));
> +static char *x_strdup(const char *, const char *, int)
> +    __attribute__((__malloc__(free), __nonnull__));
> +static char *x_strndup(const char *, size_t, const char *, int)
> +    __attribute__((__malloc__(free), __nonnull__));
> +
> +
> +/*
> + * Report a fatal error and exit.
> + */
> +static void
> +die(const char *format, ...)
> +{
> +    va_list args;
> +
> +    fflush(stdout);
> +    fprintf(stderr, "runtests: ");
> +    va_start(args, format);
> +    vfprintf(stderr, format, args);
> +    va_end(args);
> +    fprintf(stderr, "\n");
> +    exit(1);
> +}
> +
> +
> +/*
> + * Report a fatal error, including the results of strerror, and exit.
> + */
> +static void
> +sysdie(const char *format, ...)
> +{
> +    int oerrno;
> +    va_list args;
> +
> +    oerrno = errno;
> +    fflush(stdout);
> +    fprintf(stderr, "runtests: ");
> +    va_start(args, format);
> +    vfprintf(stderr, format, args);
> +    va_end(args);
> +    fprintf(stderr, ": %s\n", strerror(oerrno));
> +    exit(1);
> +}
> +
> +
> +/*
> + * Allocate zeroed memory, reporting a fatal error and exiting on failure.
> + */
> +static void *
> +x_calloc(size_t n, size_t size, const char *file, int line)
> +{
> +    void *p;
> +
> +    n = (n > 0) ? n : 1;
> +    size = (size > 0) ? size : 1;
> +    p = calloc(n, size);
> +    if (p == NULL)
> +        sysdie("failed to calloc %lu bytes at %s line %d",
> +               (unsigned long) size, file, line);
> +    return p;
> +}
> +
> +
> +/*
> + * Allocate memory, reporting a fatal error and exiting on failure.
> + */
> +static void *
> +x_malloc(size_t size, const char *file, int line)
> +{
> +    void *p;
> +
> +    p = malloc(size);
> +    if (p == NULL)
> +        sysdie("failed to malloc %lu bytes at %s line %d",
> +               (unsigned long) size, file, line);
> +    return p;
> +}
> +
> +
> +/*
> + * Reallocate memory, reporting a fatal error and exiting on failure.
> + *
> + * We should technically use SIZE_MAX here for the overflow check, but
> + * SIZE_MAX is C99 and we're only assuming C89 + SUSv3, which does not
> + * guarantee that it exists.  They do guarantee that UINT_MAX exists, and we
> + * can assume that UINT_MAX <= SIZE_MAX.  And we should not be allocating
> + * anything anywhere near that large.
> + *
> + * (In theory, C89 and C99 permit size_t to be smaller than unsigned int, but
> + * I disbelieve in the existence of such systems and they will have to cope
> + * without overflow checks.)
> + */
> +static void *
> +x_reallocarray(void *p, size_t n, size_t size, const char *file, int line)
> +{
> +    n = (n > 0) ? n : 1;
> +    size = (size > 0) ? size : 1;
> +
> +    if (n > 0 && UINT_MAX / n <= size)
> +        sysdie("realloc too large at %s line %d", file, line);
> +    p = realloc(p, n * size);
> +    if (p == NULL)
> +        sysdie("failed to realloc %lu bytes at %s line %d",
> +               (unsigned long) (n * size), file, line);
> +    return p;
> +}
> +
> +
> +/*
> + * Copy a string, reporting a fatal error and exiting on failure.
> + */
> +static char *
> +x_strdup(const char *s, const char *file, int line)
> +{
> +    char *p;
> +    size_t len;
> +
> +    len = strlen(s) + 1;
> +    p = (char *) malloc(len);
> +    if (p == NULL)
> +        sysdie("failed to strdup %lu bytes at %s line %d", (unsigned long) len,
> +               file, line);
> +    memcpy(p, s, len);
> +    return p;
> +}
> +
> +
> +/*
> + * Copy the first n characters of a string, reporting a fatal error and
> + * existing on failure.
> + *
> + * Avoid using the system strndup function since it may not exist (on Mac OS
> + * X, for example), and there's no need to introduce another portability
> + * requirement.
> + */
> +char *
> +x_strndup(const char *s, size_t size, const char *file, int line)
> +{
> +    const char *p;
> +    size_t len;
> +    char *copy;
> +
> +    /* Don't assume that the source string is nul-terminated. */
> +    for (p = s; (size_t) (p - s) < size && *p != '\0'; p++)
> +        ;
> +    len = (size_t) (p - s);
> +    copy = (char *) malloc(len + 1);
> +    if (copy == NULL)
> +        sysdie("failed to strndup %lu bytes at %s line %d",
> +               (unsigned long) len, file, line);
> +    memcpy(copy, s, len);
> +    copy[len] = '\0';
> +    return copy;
> +}
> +
> +
> +/*
> + * Form a new string by concatenating multiple strings.  The arguments must be
> + * terminated by (const char *) 0.
> + *
> + * This function only exists because we can't assume asprintf.  We can't
> + * simulate asprintf with snprintf because we're only assuming SUSv3, which
> + * does not require that snprintf with a NULL buffer return the required
> + * length.  When those constraints are relaxed, this should be ripped out and
> + * replaced with asprintf or a more trivial replacement with snprintf.
> + */
> +static char *
> +concat(const char *first, ...)
> +{
> +    va_list args;
> +    char *result;
> +    const char *string;
> +    size_t offset;
> +    size_t length = 0;
> +
> +    /*
> +     * Find the total memory required.  Ensure we don't overflow length.  We
> +     * aren't guaranteed to have SIZE_MAX, so use UINT_MAX as an acceptable
> +     * substitute (see the x_nrealloc comments).
> +     */
> +    va_start(args, first);
> +    for (string = first; string != NULL; string = va_arg(args, const char *)) {
> +        if (length >= UINT_MAX - strlen(string)) {
> +            errno = EINVAL;
> +            sysdie("strings too long in concat");
> +        }
> +        length += strlen(string);
> +    }
> +    va_end(args);
> +    length++;
> +
> +    /* Create the string. */
> +    result = xmalloc(length);
> +    va_start(args, first);
> +    offset = 0;
> +    for (string = first; string != NULL; string = va_arg(args, const char *)) {
> +        memcpy(result + offset, string, strlen(string));
> +        offset += strlen(string);
> +    }
> +    va_end(args);
> +    result[offset] = '\0';
> +    return result;
> +}
> +
> +
> +/*
> + * Given a struct timeval, return the number of seconds it represents as a
> + * double.  Use difftime() to convert a time_t to a double.
> + */
> +static double
> +tv_seconds(const struct timeval *tv)
> +{
> +    return difftime(tv->tv_sec, 0) + (double) tv->tv_usec * 1e-6;
> +}
> +
> +
> +/*
> + * Given two struct timevals, return the difference in seconds.
> + */
> +static double
> +tv_diff(const struct timeval *tv1, const struct timeval *tv0)
> +{
> +    return tv_seconds(tv1) - tv_seconds(tv0);
> +}
> +
> +
> +/*
> + * Given two struct timevals, return the sum in seconds as a double.
> + */
> +static double
> +tv_sum(const struct timeval *tv1, const struct timeval *tv2)
> +{
> +    return tv_seconds(tv1) + tv_seconds(tv2);
> +}
> +
> +
> +/*
> + * Given a pointer to a string, skip any leading whitespace and return a
> + * pointer to the first non-whitespace character.
> + */
> +static const char *
> +skip_whitespace(const char *p)
> +{
> +    while (isspace((unsigned char) (*p)))
> +        p++;
> +    return p;
> +}
> +
> +
> +/*
> + * Given a pointer to a string, skip any non-whitespace characters and return
> + * a pointer to the first whitespace character, or to the end of the string.
> + */
> +static const char *
> +skip_non_whitespace(const char *p)
> +{
> +    while (*p != '\0' && !isspace((unsigned char) (*p)))
> +        p++;
> +    return p;
> +}
> +
> +
> +/*
> + * Start a program, connecting its stdout to a pipe on our end and its stderr
> + * to /dev/null, and storing the file descriptor to read from in the two
> + * argument.  Returns the PID of the new process.  Errors are fatal.
> + */
> +static pid_t
> +test_start(char *const *command, int *fd)
> +{
> +    int fds[2], infd, errfd;
> +    pid_t child;
> +
> +    /* Create a pipe used to capture the output from the test program. */
> +    if (pipe(fds) == -1) {
> +        puts("ABORTED");
> +        fflush(stdout);
> +        sysdie("can't create pipe");
> +    }
> +
> +    /* Fork a child process, massage the file descriptors, and exec. */
> +    child = fork();
> +    switch (child) {
> +    case -1:
> +        puts("ABORTED");
> +        fflush(stdout);
> +        sysdie("can't fork");
> +
> +    /* In the child.  Set up our standard output. */
> +    case 0:
> +        close(fds[0]);
> +        close(STDOUT_FILENO);
> +        if (dup2(fds[1], STDOUT_FILENO) < 0)
> +            _exit(CHILDERR_DUP);
> +        close(fds[1]);
> +
> +        /* Point standard input at /dev/null. */
> +        close(STDIN_FILENO);
> +        infd = open("/dev/null", O_RDONLY);
> +        if (infd < 0)
> +            _exit(CHILDERR_STDIN);
> +        if (infd != STDIN_FILENO) {
> +            if (dup2(infd, STDIN_FILENO) < 0)
> +                _exit(CHILDERR_DUP);
> +            close(infd);
> +        }
> +
> +        /* Point standard error at /dev/null. */
> +        close(STDERR_FILENO);
> +        errfd = open("/dev/null", O_WRONLY);
> +        if (errfd < 0)
> +            _exit(CHILDERR_STDERR);
> +        if (errfd != STDERR_FILENO) {
> +            if (dup2(errfd, STDERR_FILENO) < 0)
> +                _exit(CHILDERR_DUP);
> +            close(errfd);
> +        }
> +
> +        /* Now, exec our process. */
> +        if (execv(command[0], command) == -1)
> +            _exit(CHILDERR_EXEC);
> +        break;
> +
> +    /* In parent.  Close the extra file descriptor. */
> +    default:
> +        close(fds[1]);
> +        break;
> +    }
> +    *fd = fds[0];
> +    return child;
> +}
> +
> +
> +/*
> + * Back up over the output saying what test we were executing.
> + */
> +static void
> +test_backspace(struct testset *ts)
> +{
> +    unsigned int i;
> +
> +    if (!isatty(STDOUT_FILENO))
> +        return;
> +    for (i = 0; i < ts->length; i++)
> +        putchar('\b');
> +    for (i = 0; i < ts->length; i++)
> +        putchar(' ');
> +    for (i = 0; i < ts->length; i++)
> +        putchar('\b');
> +    ts->length = 0;
> +}
> +
> +
> +/*
> + * Allocate or resize the array of test results to be large enough to contain
> + * the test number in.
> + */
> +static void
> +resize_results(struct testset *ts, unsigned long n)
> +{
> +    unsigned long i;
> +    size_t s;
> +
> +    /* If there's already enough space, return quickly. */
> +    if (n <= ts->allocated)
> +        return;
> +
> +    /*
> +     * If no space has been allocated, do the initial allocation.  Otherwise,
> +     * resize.  Start with 32 test cases and then add 1024 with each resize to
> +     * try to reduce the number of reallocations.
> +     */
> +    if (ts->allocated == 0) {
> +        s = (n > 32) ? n : 32;
> +        ts->results = xcalloc(s, enum test_status);
> +    } else {
> +        s = (n > ts->allocated + 1024) ? n : ts->allocated + 1024;
> +        ts->results = xreallocarray(ts->results, s, enum test_status);
> +    }
> +
> +    /* Set the results for the newly-allocated test array. */
> +    for (i = ts->allocated; i < s; i++)
> +        ts->results[i] = TEST_INVALID;
> +    ts->allocated = s;
> +}
> +
> +
> +/*
> + * Report an invalid test number and set the appropriate flags.  Pulled into a
> + * separate function since we do this in several places.
> + */
> +static void
> +invalid_test_number(struct testset *ts, long n, enum test_verbose verbose)
> +{
> +    if (!verbose)
> +        test_backspace(ts);
> +    printf("ABORTED (invalid test number %ld)\n", n);
> +    ts->aborted = 1;
> +    ts->reported = 1;
> +}
> +
> +
> +/*
> + * Read the plan line of test output, which should contain the range of test
> + * numbers.  We may initialize the testset structure here if we haven't yet
> + * seen a test.  Return true if initialization succeeded and the test should
> + * continue, false otherwise.
> + */
> +static int
> +test_plan(const char *line, struct testset *ts, enum test_verbose verbose)
> +{
> +    long n;
> +
> +    /*
> +     * Accept a plan without the leading 1.. for compatibility with older
> +     * versions of runtests.  This will only be allowed if we've not yet seen
> +     * a test result.
> +     */
> +    line = skip_whitespace(line);
> +    if (strncmp(line, "1..", 3) == 0)
> +        line += 3;
> +
> +    /*
> +     * Get the count and check it for validity.
> +     *
> +     * If we have something of the form "1..0 # skip foo", the whole file was
> +     * skipped; record that.  If we do skip the whole file, zero out all of
> +     * our statistics, since they're no longer relevant.
> +     *
> +     * strtol is called with a second argument to advance the line pointer
> +     * past the count to make it simpler to detect the # skip case.
> +     */
> +    n = strtol(line, (char **) &line, 10);
> +    if (n == 0) {
> +        line = skip_whitespace(line);
> +        if (*line == '#') {
> +            line = skip_whitespace(line + 1);
> +            if (strncasecmp(line, "skip", 4) == 0) {
> +                line = skip_whitespace(line + 4);
> +                if (*line != '\0') {
> +                    ts->reason = xstrdup(line);
> +                    ts->reason[strlen(ts->reason) - 1] = '\0';
> +                }
> +                ts->all_skipped = 1;
> +                ts->aborted = 1;
> +                ts->count = 0;
> +                ts->passed = 0;
> +                ts->skipped = 0;
> +                ts->failed = 0;
> +                return 0;
> +            }
> +        }
> +    }
> +    if (n <= 0) {
> +        puts("ABORTED (invalid test count)");
> +        ts->aborted = 1;
> +        ts->reported = 1;
> +        return 0;
> +    }
> +
> +    /*
> +     * If we are doing lazy planning, check the plan against the largest test
> +     * number that we saw and fail now if we saw a check outside the plan
> +     * range.
> +     */
> +    if (ts->plan == PLAN_PENDING && (unsigned long) n < ts->count) {
> +        invalid_test_number(ts, (long) ts->count, verbose);
> +        return 0;
> +    }
> +
> +    /*
> +     * Otherwise, allocated or resize the results if needed and update count,
> +     * and then record that we've seen a plan.
> +     */
> +    resize_results(ts, (unsigned long) n);
> +    ts->count = (unsigned long) n;
> +    if (ts->plan == PLAN_INIT)
> +        ts->plan = PLAN_FIRST;
> +    else if (ts->plan == PLAN_PENDING)
> +        ts->plan = PLAN_FINAL;
> +    return 1;
> +}
> +
> +
> +/*
> + * Given a single line of output from a test, parse it and return the success
> + * status of that test.  Anything printed to stdout not matching the form
> + * /^(not )?ok \d+/ is ignored.  Sets ts->current to the test number that just
> + * reported status.
> + */
> +static void
> +test_checkline(const char *line, struct testset *ts, enum test_verbose verbose)
> +{
> +    enum test_status status = TEST_PASS;
> +    const char *bail;
> +    char *end;
> +    long number;
> +    unsigned long current;
> +    int outlen;
> +
> +    /* Before anything, check for a test abort. */
> +    bail = strstr(line, "Bail out!");
> +    if (bail != NULL) {
> +        bail = skip_whitespace(bail + strlen("Bail out!"));
> +        if (*bail != '\0') {
> +            size_t length;
> +
> +            length = strlen(bail);
> +            if (bail[length - 1] == '\n')
> +                length--;
> +            if (!verbose)
> +                test_backspace(ts);
> +            printf("ABORTED (%.*s)\n", (int) length, bail);
> +            ts->reported = 1;
> +        }
> +        ts->aborted = 1;
> +        return;
> +    }
> +
> +    /*
> +     * If the given line isn't newline-terminated, it was too big for an
> +     * fgets(), which means ignore it.
> +     */
> +    if (line[strlen(line) - 1] != '\n')
> +        return;
> +
> +    /* If the line begins with a hash mark, ignore it. */
> +    if (line[0] == '#')
> +        return;
> +
> +    /* If we haven't yet seen a plan, look for one. */
> +    if (ts->plan == PLAN_INIT && isdigit((unsigned char) (*line))) {
> +        if (!test_plan(line, ts, verbose))
> +            return;
> +    } else if (strncmp(line, "1..", 3) == 0) {
> +        if (ts->plan == PLAN_PENDING) {
> +            if (!test_plan(line, ts, verbose))
> +                return;
> +        } else {
> +            if (!verbose)
> +                test_backspace(ts);
> +            puts("ABORTED (multiple plans)");
> +            ts->aborted = 1;
> +            ts->reported = 1;
> +            return;
> +        }
> +    }
> +
> +    /* Parse the line, ignoring something we can't parse. */
> +    if (strncmp(line, "not ", 4) == 0) {
> +        status = TEST_FAIL;
> +        line += 4;
> +    }
> +    if (strncmp(line, "ok", 2) != 0)
> +        return;
> +    line = skip_whitespace(line + 2);
> +    errno = 0;
> +    number = strtol(line, &end, 10);
> +    if (errno != 0 || end == line)
> +        current = ts->current + 1;
> +    else if (number <= 0) {
> +        invalid_test_number(ts, number, verbose);
> +        return;
> +    } else
> +        current = (unsigned long) number;
> +    if (current > ts->count && ts->plan == PLAN_FIRST) {
> +        invalid_test_number(ts, (long) current, verbose);
> +        return;
> +    }
> +
> +    /* We have a valid test result.  Tweak the results array if needed. */
> +    if (ts->plan == PLAN_INIT || ts->plan == PLAN_PENDING) {
> +        ts->plan = PLAN_PENDING;
> +        resize_results(ts, current);
> +        if (current > ts->count)
> +            ts->count = current;
> +    }
> +
> +    /*
> +     * Handle directives.  We should probably do something more interesting
> +     * with unexpected passes of todo tests.
> +     */
> +    while (isdigit((unsigned char) (*line)))
> +        line++;
> +    line = skip_whitespace(line);
> +    if (*line == '#') {
> +        line = skip_whitespace(line + 1);
> +        if (strncasecmp(line, "skip", 4) == 0)
> +            status = TEST_SKIP;
> +        if (strncasecmp(line, "todo", 4) == 0)
> +            status = (status == TEST_FAIL) ? TEST_SKIP : TEST_FAIL;
> +    }
> +
> +    /* Make sure that the test number is in range and not a duplicate. */
> +    if (ts->results[current - 1] != TEST_INVALID) {
> +        if (!verbose)
> +            test_backspace(ts);
> +        printf("ABORTED (duplicate test number %lu)\n", current);
> +        ts->aborted = 1;
> +        ts->reported = 1;
> +        return;
> +    }
> +
> +    /* Good results.  Increment our various counters. */
> +    switch (status) {
> +    case TEST_PASS:
> +        ts->passed++;
> +        break;
> +    case TEST_FAIL:
> +        ts->failed++;
> +        break;
> +    case TEST_SKIP:
> +        ts->skipped++;
> +        break;
> +    case TEST_INVALID:
> +        break;
> +    }
> +    ts->current = current;
> +    ts->results[current - 1] = status;
> +    if (!verbose && isatty(STDOUT_FILENO)) {
> +        test_backspace(ts);
> +        if (ts->plan == PLAN_PENDING)
> +            outlen = printf("%lu/?", current);
> +        else
> +            outlen = printf("%lu/%lu", current, ts->count);
> +        ts->length = (outlen >= 0) ? (unsigned int) outlen : 0;
> +        fflush(stdout);
> +    }
> +}
> +
> +
> +/*
> + * Print out a range of test numbers, returning the number of characters it
> + * took up.  Takes the first number, the last number, the number of characters
> + * already printed on the line, and the limit of number of characters the line
> + * can hold.  Add a comma and a space before the range if chars indicates that
> + * something has already been printed on the line, and print ... instead if
> + * chars plus the space needed would go over the limit (use a limit of 0 to
> + * disable this).
> + */
> +static unsigned int
> +test_print_range(unsigned long first, unsigned long last, unsigned long chars,
> +                 unsigned int limit)
> +{
> +    unsigned int needed = 0;
> +    unsigned long n;
> +
> +    for (n = first; n > 0; n /= 10)
> +        needed++;
> +    if (last > first) {
> +        for (n = last; n > 0; n /= 10)
> +            needed++;
> +        needed++;
> +    }
> +    if (chars > 0)
> +        needed += 2;
> +    if (limit > 0 && chars + needed > limit) {
> +        needed = 0;
> +        if (chars <= limit) {
> +            if (chars > 0) {
> +                printf(", ");
> +                needed += 2;
> +            }
> +            printf("...");
> +            needed += 3;
> +        }
> +    } else {
> +        if (chars > 0)
> +            printf(", ");
> +        if (last > first)
> +            printf("%lu-", first);
> +        printf("%lu", last);
> +    }
> +    return needed;
> +}
> +
> +
> +/*
> + * Summarize a single test set.  The second argument is 0 if the set exited
> + * cleanly, a positive integer representing the exit status if it exited
> + * with a non-zero status, and a negative integer representing the signal
> + * that terminated it if it was killed by a signal.
> + */
> +static void
> +test_summarize(struct testset *ts, int status)
> +{
> +    unsigned long i;
> +    unsigned long missing = 0;
> +    unsigned long failed = 0;
> +    unsigned long first = 0;
> +    unsigned long last = 0;
> +
> +    if (ts->aborted) {
> +        fputs("ABORTED", stdout);
> +        if (ts->count > 0)
> +            printf(" (passed %lu/%lu)", ts->passed, ts->count - ts->skipped);
> +    } else {
> +        for (i = 0; i < ts->count; i++) {
> +            if (ts->results[i] == TEST_INVALID) {
> +                if (missing == 0)
> +                    fputs("MISSED ", stdout);
> +                if (first && i == last)
> +                    last = i + 1;
> +                else {
> +                    if (first)
> +                        test_print_range(first, last, missing - 1, 0);
> +                    missing++;
> +                    first = i + 1;
> +                    last = i + 1;
> +                }
> +            }
> +        }
> +        if (first)
> +            test_print_range(first, last, missing - 1, 0);
> +        first = 0;
> +        last = 0;
> +        for (i = 0; i < ts->count; i++) {
> +            if (ts->results[i] == TEST_FAIL) {
> +                if (missing && !failed)
> +                    fputs("; ", stdout);
> +                if (failed == 0)
> +                    fputs("FAILED ", stdout);
> +                if (first && i == last)
> +                    last = i + 1;
> +                else {
> +                    if (first)
> +                        test_print_range(first, last, failed - 1, 0);
> +                    failed++;
> +                    first = i + 1;
> +                    last = i + 1;
> +                }
> +            }
> +        }
> +        if (first)
> +            test_print_range(first, last, failed - 1, 0);
> +        if (!missing && !failed) {
> +            fputs(!status ? "ok" : "dubious", stdout);
> +            if (ts->skipped > 0) {
> +                if (ts->skipped == 1)
> +                    printf(" (skipped %lu test)", ts->skipped);
> +                else
> +                    printf(" (skipped %lu tests)", ts->skipped);
> +            }
> +        }
> +    }
> +    if (status > 0)
> +        printf(" (exit status %d)", status);
> +    else if (status < 0)
> +        printf(" (killed by signal %d%s)", -status,
> +               WCOREDUMP(ts->status) ? ", core dumped" : "");
> +    putchar('\n');
> +}
> +
> +
> +/*
> + * Given a test set, analyze the results, classify the exit status, handle a
> + * few special error messages, and then pass it along to test_summarize() for
> + * the regular output.  Returns true if the test set ran successfully and all
> + * tests passed or were skipped, false otherwise.
> + */
> +static int
> +test_analyze(struct testset *ts)
> +{
> +    if (ts->reported)
> +        return 0;
> +    if (ts->all_skipped) {
> +        if (ts->reason == NULL)
> +            puts("skipped");
> +        else
> +            printf("skipped (%s)\n", ts->reason);
> +        return 1;
> +    } else if (WIFEXITED(ts->status) && WEXITSTATUS(ts->status) != 0) {
> +        switch (WEXITSTATUS(ts->status)) {
> +        case CHILDERR_DUP:
> +            if (!ts->reported)
> +                puts("ABORTED (can't dup file descriptors)");
> +            break;
> +        case CHILDERR_EXEC:
> +            if (!ts->reported)
> +                puts("ABORTED (execution failed -- not found?)");
> +            break;
> +        case CHILDERR_STDIN:
> +        case CHILDERR_STDERR:
> +            if (!ts->reported)
> +                puts("ABORTED (can't open /dev/null)");
> +            break;
> +        default:
> +            test_summarize(ts, WEXITSTATUS(ts->status));
> +            break;
> +        }
> +        return 0;
> +    } else if (WIFSIGNALED(ts->status)) {
> +        test_summarize(ts, -WTERMSIG(ts->status));
> +        return 0;
> +    } else if (ts->plan != PLAN_FIRST && ts->plan != PLAN_FINAL) {
> +        puts("ABORTED (no valid test plan)");
> +        ts->aborted = 1;
> +        return 0;
> +    } else {
> +        test_summarize(ts, 0);
> +        return (ts->failed == 0);
> +    }
> +}
> +
> +
> +/*
> + * Runs a single test set, accumulating and then reporting the results.
> + * Returns true if the test set was successfully run and all tests passed,
> + * false otherwise.
> + */
> +static int
> +test_run(struct testset *ts, enum test_verbose verbose)
> +{
> +    pid_t testpid, child;
> +    int outfd, status;
> +    unsigned long i;
> +    FILE *output;
> +    char buffer[BUFSIZ];
> +
> +    /* Run the test program. */
> +    testpid = test_start(ts->command, &outfd);
> +    output = fdopen(outfd, "r");
> +    if (!output) {
> +        puts("ABORTED");
> +        fflush(stdout);
> +        sysdie("fdopen failed");
> +    }
> +
> +    /*
> +     * Pass each line of output to test_checkline(), and print the line if
> +     * verbosity is requested.
> +     */
> +    while (!ts->aborted && fgets(buffer, sizeof(buffer), output)) {
> +        if (verbose)
> +            printf("%s", buffer);
> +        test_checkline(buffer, ts, verbose);
> +    }
> +    if (ferror(output) || ts->plan == PLAN_INIT)
> +        ts->aborted = 1;
> +    if (!verbose)
> +        test_backspace(ts);
> +
> +    /*
> +     * Consume the rest of the test output, close the output descriptor,
> +     * retrieve the exit status, and pass that information to test_analyze()
> +     * for eventual output.
> +     */
> +    while (fgets(buffer, sizeof(buffer), output))
> +        if (verbose)
> +            printf("%s", buffer);
> +    fclose(output);
> +    child = waitpid(testpid, &ts->status, 0);
> +    if (child == (pid_t) -1) {
> +        if (!ts->reported) {
> +            puts("ABORTED");
> +            fflush(stdout);
> +        }
> +        sysdie("waitpid for %u failed", (unsigned int) testpid);
> +    }
> +    if (ts->all_skipped)
> +        ts->aborted = 0;
> +    status = test_analyze(ts);
> +
> +    /* Convert missing tests to failed tests. */
> +    for (i = 0; i < ts->count; i++) {
> +        if (ts->results[i] == TEST_INVALID) {
> +            ts->failed++;
> +            ts->results[i] = TEST_FAIL;
> +            status = 0;
> +        }
> +    }
> +    return status;
> +}
> +
> +
> +/* Summarize a list of test failures. */
> +static void
> +test_fail_summary(const struct testlist *fails)
> +{
> +    struct testset *ts;
> +    unsigned int chars;
> +    unsigned long i, first, last, total;
> +    double failed;
> +
> +    puts(header);
> +
> +    /* Failed Set                 Fail/Total (%) Skip Stat  Failing (25)
> +       -------------------------- -------------- ---- ----  -------------- */
> +    for (; fails; fails = fails->next) {
> +        ts = fails->ts;
> +        total = ts->count - ts->skipped;
> +        failed = (double) ts->failed;
> +        printf("%-26.26s %4lu/%-4lu %3.0f%% %4lu ", ts->file, ts->failed,
> +               total, total ? (failed * 100.0) / (double) total : 0,
> +               ts->skipped);
> +        if (WIFEXITED(ts->status))
> +            printf("%4d  ", WEXITSTATUS(ts->status));
> +        else
> +            printf("  --  ");
> +        if (ts->aborted) {
> +            puts("aborted");
> +            continue;
> +        }
> +        chars = 0;
> +        first = 0;
> +        last = 0;
> +        for (i = 0; i < ts->count; i++) {
> +            if (ts->results[i] == TEST_FAIL) {
> +                if (first != 0 && i == last)
> +                    last = i + 1;
> +                else {
> +                    if (first != 0)
> +                        chars += test_print_range(first, last, chars, 19);
> +                    first = i + 1;
> +                    last = i + 1;
> +                }
> +            }
> +        }
> +        if (first != 0)
> +            test_print_range(first, last, chars, 19);
> +        putchar('\n');
> +    }
> +}
> +
> +
> +/*
> + * Check whether a given file path is a valid test.  Currently, this checks
> + * whether it is executable and is a regular file.  Returns true or false.
> + */
> +static int
> +is_valid_test(const char *path)
> +{
> +    struct stat st;
> +
> +    if (access(path, X_OK) < 0)
> +        return 0;
> +    if (stat(path, &st) < 0)
> +        return 0;
> +    if (!S_ISREG(st.st_mode))
> +        return 0;
> +    return 1;
> +}
> +
> +
> +/*
> + * Given the name of a test, a pointer to the testset struct, and the source
> + * and build directories, find the test.  We try first relative to the current
> + * directory, then in the build directory (if not NULL), then in the source
> + * directory.  In each of those directories, we first try a "-t" extension and
> + * then a ".t" extension.  When we find an executable program, we return the
> + * path to that program.  If none of those paths are executable, just fill in
> + * the name of the test as is.
> + *
> + * The caller is responsible for freeing the path member of the testset
> + * struct.
> + */
> +static char *
> +find_test(const char *name, const char *source, const char *build)
> +{
> +    char *path = NULL;
> +    const char *bases[3], *suffix, *base;
> +    unsigned int i, j;
> +    const char *suffixes[3] = {"-t", ".t", ""};
> +
> +    /* Possible base directories. */
> +    bases[0] = ".";
> +    bases[1] = build;
> +    bases[2] = source;
> +
> +    /* Try each suffix with each base. */
> +    for (i = 0; i < ARRAY_SIZE(suffixes); i++) {
> +        suffix = suffixes[i];
> +        for (j = 0; j < ARRAY_SIZE(bases); j++) {
> +            base = bases[j];
> +            if (base == NULL)
> +                continue;
> +            path = concat(base, "/", name, suffix, (const char *) 0);
> +            if (is_valid_test(path))
> +                return path;
> +            free(path);
> +            path = NULL;
> +        }
> +    }
> +    if (path == NULL)
> +        path = xstrdup(name);
> +    return path;
> +}
> +
> +
> +/*
> + * Parse a single line of a test list and store the test name and command to
> + * execute it in the given testset struct.
> + *
> + * Normally, each line is just the name of the test, which is located in the
> + * test directory and turned into a command to run.  However, each line may
> + * have whitespace-separated options, which change the command that's run.
> + * Current supported options are:
> + *
> + * valgrind
> + *     Run the test under valgrind if C_TAP_VALGRIND is set.  The contents
> + *     of that environment variable are taken as the valgrind command (with
> + *     options) to run.  The command is parsed with a simple split on
> + *     whitespace and no quoting is supported.
> + *
> + * libtool
> + *     If running under valgrind, use libtool to invoke valgrind.  This avoids
> + *     running valgrind on the wrapper shell script generated by libtool.  If
> + *     set, C_TAP_LIBTOOL must be set to the full path to the libtool program
> + *     to use to run valgrind and thus the test.  Ignored if the test isn't
> + *     being run under valgrind.
> + */
> +static void
> +parse_test_list_line(const char *line, struct testset *ts, const char *source,
> +                     const char *build)
> +{
> +    const char *p, *end, *option, *libtool;
> +    const char *valgrind = NULL;
> +    unsigned int use_libtool = 0;
> +    unsigned int use_valgrind = 0;
> +    size_t len, i;
> +
> +    /* Determine the name of the test. */
> +    p = skip_non_whitespace(line);
> +    ts->file = xstrndup(line, p - line);
> +
> +    /* Check if any test options are set. */
> +    p = skip_whitespace(p);
> +    while (*p != '\0') {
> +        end = skip_non_whitespace(p);
> +        if (strncmp(p, "libtool", end - p) == 0) {
> +            use_libtool = 1;
> +        } else if (strncmp(p, "valgrind", end - p) == 0) {
> +            valgrind = getenv("C_TAP_VALGRIND");
> +            use_valgrind = (valgrind != NULL);
> +        } else {
> +            option = xstrndup(p, end - p);
> +            die("unknown test list option %s", option);
> +        }
> +        p = skip_whitespace(end);
> +    }
> +
> +    /* Construct the argv to run the test.  First, find the length. */
> +    len = 1;
> +    if (use_valgrind && valgrind != NULL) {
> +        p = skip_whitespace(valgrind);
> +        while (*p != '\0') {
> +            len++;
> +            p = skip_whitespace(skip_non_whitespace(p));
> +        }
> +        if (use_libtool)
> +            len += 2;
> +    }
> +
> +    /* Now, build the command. */
> +    ts->command = xcalloc(len + 1, char *);
> +    i = 0;
> +    if (use_valgrind && valgrind != NULL) {
> +        if (use_libtool) {
> +            libtool = getenv("C_TAP_LIBTOOL");
> +            if (libtool == NULL)
> +                die("valgrind with libtool requested, but C_TAP_LIBTOOL is not"
> +                    " set");
> +            ts->command[i++] = xstrdup(libtool);
> +            ts->command[i++] = xstrdup("--mode=execute");
> +        }
> +        p = skip_whitespace(valgrind);
> +        while (*p != '\0') {
> +            end = skip_non_whitespace(p);
> +            ts->command[i++] = xstrndup(p, end - p);
> +            p = skip_whitespace(end);
> +        }
> +    }
> +    if (i != len - 1)
> +        die("internal error while constructing command line");
> +    ts->command[i++] = find_test(ts->file, source, build);
> +    ts->command[i] = NULL;
> +}
> +
> +
> +/*
> + * Read a list of tests from a file, returning the list of tests as a struct
> + * testlist, or NULL if there were no tests (such as a file containing only
> + * comments).  Reports an error to standard error and exits if the list of
> + * tests cannot be read.
> + */
> +static struct testlist *
> +read_test_list(const char *filename, const char *source, const char *build)
> +{
> +    FILE *file;
> +    unsigned int line;
> +    size_t length;
> +    char buffer[BUFSIZ];
> +    const char *start;
> +    struct testlist *listhead, *current;
> +
> +    /* Create the initial container list that will hold our results. */
> +    listhead = xcalloc(1, struct testlist);
> +    current = NULL;
> +
> +    /*
> +     * Open our file of tests to run and read it line by line, creating a new
> +     * struct testlist and struct testset for each line.
> +     */
> +    file = fopen(filename, "r");
> +    if (file == NULL)
> +        sysdie("can't open %s", filename);
> +    line = 0;
> +    while (fgets(buffer, sizeof(buffer), file)) {
> +        line++;
> +        length = strlen(buffer) - 1;
> +        if (buffer[length] != '\n') {
> +            fprintf(stderr, "%s:%u: line too long\n", filename, line);
> +            exit(1);
> +        }
> +        buffer[length] = '\0';
> +
> +        /* Skip comments, leading spaces, and blank lines. */
> +        start = skip_whitespace(buffer);
> +        if (strlen(start) == 0)
> +            continue;
> +        if (start[0] == '#')
> +            continue;
> +
> +        /* Allocate the new testset structure. */
> +        if (current == NULL)
> +            current = listhead;
> +        else {
> +            current->next = xcalloc(1, struct testlist);
> +            current = current->next;
> +        }
> +        current->ts = xcalloc(1, struct testset);
> +        current->ts->plan = PLAN_INIT;
> +
> +        /* Parse the line and store the results in the testset struct. */
> +        parse_test_list_line(start, current->ts, source, build);
> +    }
> +    fclose(file);
> +
> +    /* If there were no tests, current is still NULL. */
> +    if (current == NULL) {
> +        free(listhead);
> +        return NULL;
> +    }
> +
> +    /* Return the results. */
> +    return listhead;
> +}
> +
> +
> +/*
> + * Build a list of tests from command line arguments.  Takes the argv and argc
> + * representing the command line arguments and returns a newly allocated test
> + * list, or NULL if there were no tests.  The caller is responsible for
> + * freeing.
> + */
> +static struct testlist *
> +build_test_list(char *argv[], int argc, const char *source, const char *build)
> +{
> +    int i;
> +    struct testlist *listhead, *current;
> +
> +    /* Create the initial container list that will hold our results. */
> +    listhead = xcalloc(1, struct testlist);
> +    current = NULL;
> +
> +    /* Walk the list of arguments and create test sets for them. */
> +    for (i = 0; i < argc; i++) {
> +        if (current == NULL)
> +            current = listhead;
> +        else {
> +            current->next = xcalloc(1, struct testlist);
> +            current = current->next;
> +        }
> +        current->ts = xcalloc(1, struct testset);
> +        current->ts->plan = PLAN_INIT;
> +        current->ts->file = xstrdup(argv[i]);
> +        current->ts->command = xcalloc(2, char *);
> +        current->ts->command[0] = find_test(current->ts->file, source, build);
> +        current->ts->command[1] = NULL;
> +    }
> +
> +    /* If there were no tests, current is still NULL. */
> +    if (current == NULL) {
> +        free(listhead);
> +        return NULL;
> +    }
> +
> +    /* Return the results. */
> +    return listhead;
> +}
> +
> +
> +/* Free a struct testset. */
> +static void
> +free_testset(struct testset *ts)
> +{
> +    size_t i;
> +
> +    free(ts->file);
> +    for (i = 0; ts->command[i] != NULL; i++)
> +        free(ts->command[i]);
> +    free(ts->command);
> +    free(ts->results);
> +    free(ts->reason);
> +    free(ts);
> +}
> +
> +
> +/*
> + * Run a batch of tests.  Takes two additional parameters: the root of the
> + * source directory and the root of the build directory.  Test programs will
> + * be first searched for in the current directory, then the build directory,
> + * then the source directory.  Returns true iff all tests passed, and always
> + * frees the test list that's passed in.
> + */
> +static int
> +test_batch(struct testlist *tests, enum test_verbose verbose)
> +{
> +    size_t length, i;
> +    size_t longest = 0;
> +    unsigned int count = 0;
> +    struct testset *ts;
> +    struct timeval start, end;
> +    struct rusage stats;
> +    struct testlist *failhead = NULL;
> +    struct testlist *failtail = NULL;
> +    struct testlist *current, *next;
> +    int succeeded;
> +    unsigned long total = 0;
> +    unsigned long passed = 0;
> +    unsigned long skipped = 0;
> +    unsigned long failed = 0;
> +    unsigned long aborted = 0;
> +
> +    /* Walk the list of tests to find the longest name. */
> +    for (current = tests; current != NULL; current = current->next) {
> +        length = strlen(current->ts->file);
> +        if (length > longest)
> +            longest = length;
> +    }
> +
> +    /*
> +     * Add two to longest and round up to the nearest tab stop.  This is how
> +     * wide the column for printing the current test name will be.
> +     */
> +    longest += 2;
> +    if (longest % 8)
> +        longest += 8 - (longest % 8);
> +
> +    /* Start the wall clock timer. */
> +    gettimeofday(&start, NULL);
> +
> +    /* Now, plow through our tests again, running each one. */
> +    for (current = tests; current != NULL; current = current->next) {
> +        ts = current->ts;
> +
> +        /* Print out the name of the test file. */
> +        fputs(ts->file, stdout);
> +        if (verbose)
> +            fputs("\n\n", stdout);
> +        else
> +            for (i = strlen(ts->file); i < longest; i++)
> +                putchar('.');
> +        if (isatty(STDOUT_FILENO))
> +            fflush(stdout);
> +
> +        /* Run the test. */
> +        succeeded = test_run(ts, verbose);
> +        fflush(stdout);
> +        if (verbose)
> +            putchar('\n');
> +
> +        /* Record cumulative statistics. */
> +        aborted += ts->aborted;
> +        total += ts->count + ts->all_skipped;
> +        passed += ts->passed;
> +        skipped += ts->skipped + ts->all_skipped;
> +        failed += ts->failed;
> +        count++;
> +
> +        /* If the test fails, we shuffle it over to the fail list. */
> +        if (!succeeded) {
> +            if (failhead == NULL) {
> +                failhead = xcalloc(1, struct testlist);
> +                failtail = failhead;
> +            } else {
> +                failtail->next = xcalloc(1, struct testlist);
> +                failtail = failtail->next;
> +            }
> +            failtail->ts = ts;
> +            failtail->next = NULL;
> +        }
> +    }
> +    total -= skipped;
> +
> +    /* Stop the timer and get our child resource statistics. */
> +    gettimeofday(&end, NULL);
> +    getrusage(RUSAGE_CHILDREN, &stats);
> +
> +    /* Summarize the failures and free the failure list. */
> +    if (failhead != NULL) {
> +        test_fail_summary(failhead);
> +        while (failhead != NULL) {
> +            next = failhead->next;
> +            free(failhead);
> +            failhead = next;
> +        }
> +    }
> +
> +    /* Free the memory used by the test lists. */
> +    while (tests != NULL) {
> +        next = tests->next;
> +        free_testset(tests->ts);
> +        free(tests);
> +        tests = next;
> +    }
> +
> +    /* Print out the final test summary. */
> +    putchar('\n');
> +    if (aborted != 0) {
> +        if (aborted == 1)
> +            printf("Aborted %lu test set", aborted);
> +        else
> +            printf("Aborted %lu test sets", aborted);
> +        printf(", passed %lu/%lu tests", passed, total);
> +    } else if (failed == 0)
> +        fputs("All tests successful", stdout);
> +    else
> +        printf("Failed %lu/%lu tests, %.2f%% okay", failed, total,
> +               (double) (total - failed) * 100.0 / (double) total);
> +    if (skipped != 0) {
> +        if (skipped == 1)
> +            printf(", %lu test skipped", skipped);
> +        else
> +            printf(", %lu tests skipped", skipped);
> +    }
> +    puts(".");
> +    printf("Files=%u,  Tests=%lu", count, total);
> +    printf(",  %.2f seconds", tv_diff(&end, &start));
> +    printf(" (%.2f usr + %.2f sys = %.2f CPU)\n", tv_seconds(&stats.ru_utime),
> +           tv_seconds(&stats.ru_stime),
> +           tv_sum(&stats.ru_utime, &stats.ru_stime));
> +    return (failed == 0 && aborted == 0);
> +}
> +
> +
> +/*
> + * Run a single test case.  This involves just running the test program after
> + * having done the environment setup and finding the test program.
> + */
> +static void
> +test_single(const char *program, const char *source, const char *build)
> +{
> +    char *path;
> +
> +    path = find_test(program, source, build);
> +    if (execl(path, path, (char *) 0) == -1)
> +        sysdie("cannot exec %s", path);
> +}
> +
> +
> +/*
> + * Main routine.  Set the C_TAP_SOURCE, C_TAP_BUILD, SOURCE, and BUILD
> + * environment variables and then, given a file listing tests, run each test
> + * listed.
> + */
> +int
> +main(int argc, char *argv[])
> +{
> +    int option;
> +    int status = 0;
> +    int single = 0;
> +    enum test_verbose verbose = CONCISE;
> +    char *c_tap_source_env = NULL;
> +    char *c_tap_build_env = NULL;
> +    char *source_env = NULL;
> +    char *build_env = NULL;
> +    const char *program;
> +    const char *shortlist;
> +    const char *list = NULL;
> +    const char *source = C_TAP_SOURCE;
> +    const char *build = C_TAP_BUILD;
> +    struct testlist *tests;
> +
> +    program = argv[0];
> +    while ((option = getopt(argc, argv, "b:hl:os:v")) != EOF) {
> +        switch (option) {
> +        case 'b':
> +            build = optarg;
> +            break;
> +        case 'h':
> +            printf(usage_message, program, program, program, usage_extra);
> +            exit(0);
> +        case 'l':
> +            list = optarg;
> +            break;
> +        case 'o':
> +            single = 1;
> +            break;
> +        case 's':
> +            source = optarg;
> +            break;
> +        case 'v':
> +            verbose = VERBOSE;
> +            break;
> +        default:
> +            exit(1);
> +        }
> +    }
> +    argv += optind;
> +    argc -= optind;
> +    if ((list == NULL && argc < 1) || (list != NULL && argc > 0)) {
> +        fprintf(stderr, usage_message, program, program, program, usage_extra);
> +        exit(1);
> +    }
> +
> +    /*
> +     * If C_TAP_VERBOSE is set in the environment, that also turns on verbose
> +     * mode.
> +     */
> +    if (getenv("C_TAP_VERBOSE") != NULL)
> +        verbose = VERBOSE;
> +
> +    /*
> +     * Set C_TAP_SOURCE and C_TAP_BUILD environment variables.  Also set
> +     * SOURCE and BUILD for backward compatibility, although we're trying to
> +     * migrate to the ones with a C_TAP_* prefix.
> +     */
> +    if (source != NULL) {
> +        c_tap_source_env = concat("C_TAP_SOURCE=", source, (const char *) 0);
> +        if (putenv(c_tap_source_env) != 0)
> +            sysdie("cannot set C_TAP_SOURCE in the environment");
> +        source_env = concat("SOURCE=", source, (const char *) 0);
> +        if (putenv(source_env) != 0)
> +            sysdie("cannot set SOURCE in the environment");
> +    }
> +    if (build != NULL) {
> +        c_tap_build_env = concat("C_TAP_BUILD=", build, (const char *) 0);
> +        if (putenv(c_tap_build_env) != 0)
> +            sysdie("cannot set C_TAP_BUILD in the environment");
> +        build_env = concat("BUILD=", build, (const char *) 0);
> +        if (putenv(build_env) != 0)
> +            sysdie("cannot set BUILD in the environment");
> +    }
> +
> +    /* Run the tests as instructed. */
> +    if (single)
> +        test_single(argv[0], source, build);
> +    else if (list != NULL) {
> +        shortlist = strrchr(list, '/');
> +        if (shortlist == NULL)
> +            shortlist = list;
> +        else
> +            shortlist++;
> +        printf(banner, shortlist);
> +        tests = read_test_list(list, source, build);
> +        status = test_batch(tests, verbose) ? 0 : 1;
> +    } else {
> +        tests = build_test_list(argv, argc, source, build);
> +        status = test_batch(tests, verbose) ? 0 : 1;
> +    }
> +
> +    /* For valgrind cleanliness, free all our memory. */
> +    if (source_env != NULL) {
> +        putenv((char *) "C_TAP_SOURCE=");
> +        putenv((char *) "SOURCE=");
> +        free(c_tap_source_env);
> +        free(source_env);
> +    }
> +    if (build_env != NULL) {
> +        putenv((char *) "C_TAP_BUILD=");
> +        putenv((char *) "BUILD=");
> +        free(c_tap_build_env);
> +        free(build_env);
> +    }
> +    exit(status);
> +}
> \ No newline at end of file
> diff --git a/t/tap/basic.c b/t/tap/basic.c
> new file mode 100644
> index 0000000000..704282b9c1
> --- /dev/null
> +++ b/t/tap/basic.c
> @@ -0,0 +1,1029 @@
> +/*
> + * Some utility routines for writing tests.
> + *
> + * Here are a variety of utility routines for writing tests compatible with
> + * the TAP protocol.  All routines of the form ok() or is*() take a test
> + * number and some number of appropriate arguments, check to be sure the
> + * results match the expected output using the arguments, and print out
> + * something appropriate for that test number.  Other utility routines help in
> + * constructing more complex tests, skipping tests, reporting errors, setting
> + * up the TAP output format, or finding things in the test environment.
> + *
> + * This file is part of C TAP Harness.  The current version plus supporting
> + * documentation is at <https://www.eyrie.org/~eagle/software/c-tap-harness/>.
> + *
> + * Written by Russ Allbery <[email-masked]>
> + * Copyright 2009-2019, 2021 Russ Allbery <[email-masked]>
> + * Copyright 2001-2002, 2004-2008, 2011-2014
> + *     The Board of Trustees of the Leland Stanford Junior University
> + *
> + * Permission is hereby granted, free of charge, to any person obtaining a
> + * copy of this software and associated documentation files (the "Software"),
> + * to deal in the Software without restriction, including without limitation
> + * the rights to use, copy, modify, merge, publish, distribute, sublicense,
> + * and/or sell copies of the Software, and to permit persons to whom the
> + * Software is furnished to do so, subject to the following conditions:
> + *
> + * The above copyright notice and this permission notice shall be included in
> + * all copies or substantial portions of the Software.
> + *
> + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
> + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
> + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
> + * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
> + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
> + * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
> + * DEALINGS IN THE SOFTWARE.
> + *
> + * SPDX-License-Identifier: MIT
> + */
> +
> +#include <errno.h>
> +#include <limits.h>
> +#include <stdarg.h>
> +#include <stdio.h>
> +#include <stdlib.h>
> +#include <string.h>
> +#ifdef _WIN32
> +#    include <direct.h>
> +#else
> +#    include <sys/stat.h>
> +#endif
> +#include <sys/types.h>
> +#include <unistd.h>
> +
> +#include <tap/basic.h>
> +
> +/* Windows provides mkdir and rmdir under different names. */
> +#ifdef _WIN32
> +#    define mkdir(p, m) _mkdir(p)
> +#    define rmdir(p)    _rmdir(p)
> +#endif
> +
> +/*
> + * The test count.  Always contains the number that will be used for the next
> + * test status.  This is exported to callers of the library.
> + */
> +unsigned long testnum = 1;
> +
> +/*
> + * Status information stored so that we can give a test summary at the end of
> + * the test case.  We store the planned final test and the count of failures.
> + * We can get the highest test count from testnum.
> + */
> +static unsigned long _planned = 0;
> +static unsigned long _failed = 0;
> +
> +/*
> + * Store the PID of the process that called plan() and only summarize
> + * results when that process exits, so as to not misreport results in forked
> + * processes.
> + */
> +static pid_t _process = 0;
> +
> +/*
> + * If true, we're doing lazy planning and will print out the plan based on the
> + * last test number at the end of testing.
> + */
> +static int _lazy = 0;
> +
> +/*
> + * If true, the test was aborted by calling bail().  Currently, this is only
> + * used to ensure that we pass a false value to any cleanup functions even if
> + * all tests to that point have passed.
> + */
> +static int _aborted = 0;
> +
> +/*
> + * Registered cleanup functions.  These are stored as a linked list and run in
> + * registered order by finish when the test program exits.  Each function is
> + * passed a boolean value indicating whether all tests were successful.
> + */
> +struct cleanup_func {
> +    test_cleanup_func func;
> +    test_cleanup_func_with_data func_with_data;
> +    void *data;
> +    struct cleanup_func *next;
> +};
> +static struct cleanup_func *cleanup_funcs = NULL;
> +
> +/*
> + * Registered diag files.  Any output found in these files will be printed out
> + * as if it were passed to diag() before any other output we do.  This allows
> + * background processes to log to a file and have that output interleaved with
> + * the test output.
> + */
> +struct diag_file {
> +    char *name;
> +    FILE *file;
> +    char *buffer;
> +    size_t bufsize;
> +    struct diag_file *next;
> +};
> +static struct diag_file *diag_files = NULL;
> +
> +/*
> + * Print a specified prefix and then the test description.  Handles turning
> + * the argument list into a va_args structure suitable for passing to
> + * print_desc, which has to be done in a macro.  Assumes that format is the
> + * argument immediately before the variadic arguments.
> + */
> +#define PRINT_DESC(prefix, format)  \
> +    do {                            \
> +        if (format != NULL) {       \
> +            va_list args;           \
> +            printf("%s", prefix);   \
> +            va_start(args, format); \
> +            vprintf(format, args);  \
> +            va_end(args);           \
> +        }                           \
> +    } while (0)
> +
> +
> +/*
> + * Form a new string by concatenating multiple strings.  The arguments must be
> + * terminated by (const char *) 0.
> + *
> + * This function only exists because we can't assume asprintf.  We can't
> + * simulate asprintf with snprintf because we're only assuming SUSv3, which
> + * does not require that snprintf with a NULL buffer return the required
> + * length.  When those constraints are relaxed, this should be ripped out and
> + * replaced with asprintf or a more trivial replacement with snprintf.
> + */
> +static char *
> +concat(const char *first, ...)
> +{
> +    va_list args;
> +    char *result;
> +    const char *string;
> +    size_t offset;
> +    size_t length = 0;
> +
> +    /*
> +     * Find the total memory required.  Ensure we don't overflow length.  See
> +     * the comment for breallocarray for why we're using UINT_MAX here.
> +     */
> +    va_start(args, first);
> +    for (string = first; string != NULL; string = va_arg(args, const char *)) {
> +        if (length >= UINT_MAX - strlen(string))
> +            bail("strings too long in concat");
> +        length += strlen(string);
> +    }
> +    va_end(args);
> +    length++;
> +
> +    /* Create the string. */
> +    result = bcalloc_type(length, char);
> +    va_start(args, first);
> +    offset = 0;
> +    for (string = first; string != NULL; string = va_arg(args, const char *)) {
> +        memcpy(result + offset, string, strlen(string));
> +        offset += strlen(string);
> +    }
> +    va_end(args);
> +    result[offset] = '\0';
> +    return result;
> +}
> +
> +
> +/*
> + * Helper function for check_diag_files to handle a single line in a diag
> + * file.
> + *
> + * The general scheme here used is as follows: read one line of output.  If we
> + * get NULL, check for an error.  If there was one, bail out of the test
> + * program; otherwise, return, and the enclosing loop will check for EOF.
> + *
> + * If we get some data, see if it ends in a newline.  If it doesn't end in a
> + * newline, we have one of two cases: our buffer isn't large enough, in which
> + * case we resize it and try again, or we have incomplete data in the file, in
> + * which case we rewind the file and will try again next time.
> + *
> + * Returns a boolean indicating whether the last line was incomplete.
> + */
> +static int
> +handle_diag_file_line(struct diag_file *file, fpos_t where)
> +{
> +    int size;
> +    size_t length;
> +
> +    /* Read the next line from the file. */
> +    size = file->bufsize > INT_MAX ? INT_MAX : (int) file->bufsize;
> +    if (fgets(file->buffer, size, file->file) == NULL) {
> +        if (ferror(file->file))
> +            sysbail("cannot read from %s", file->name);
> +        return 0;
> +    }
> +
> +    /*
> +     * See if the line ends in a newline.  If not, see which error case we
> +     * have.
> +     */
> +    length = strlen(file->buffer);
> +    if (file->buffer[length - 1] != '\n') {
> +        int incomplete = 0;
> +
> +        /* Check whether we ran out of buffer space and resize if so. */
> +        if (length < file->bufsize - 1)
> +            incomplete = 1;
> +        else {
> +            file->bufsize += BUFSIZ;
> +            file->buffer =
> +                breallocarray_type(file->buffer, file->bufsize, char);
> +        }
> +
> +        /*
> +         * On either incomplete lines or too small of a buffer, rewind
> +         * and read the file again (on the next pass, if incomplete).
> +         * It's simpler than trying to double-buffer the file.
> +         */
> +        if (fsetpos(file->file, &where) < 0)
> +            sysbail("cannot set position in %s", file->name);
> +        return incomplete;
> +    }
> +
> +    /* We saw a complete line.  Print it out. */
> +    printf("# %s", file->buffer);
> +    return 0;
> +}
> +
> +
> +/*
> + * Check all registered diag_files for any output.  We only print out the
> + * output if we see a complete line; otherwise, we wait for the next newline.
> + */
> +static void
> +check_diag_files(void)
> +{
> +    struct diag_file *file;
> +    fpos_t where;
> +    int incomplete;
> +
> +    /*
> +     * Walk through each file and read each line of output available.
> +     */
> +    for (file = diag_files; file != NULL; file = file->next) {
> +        clearerr(file->file);
> +
> +        /* Store the current position in case we have to rewind. */
> +        if (fgetpos(file->file, &where) < 0)
> +            sysbail("cannot get position in %s", file->name);
> +
> +        /* Continue until we get EOF or an incomplete line of data. */
> +        incomplete = 0;
> +        while (!feof(file->file) && !incomplete) {
> +            incomplete = handle_diag_file_line(file, where);
> +        }
> +    }
> +}
> +
> +
> +/*
> + * Our exit handler.  Called on completion of the test to report a summary of
> + * results provided we're still in the original process.  This also handles
> + * printing out the plan if we used plan_lazy(), although that's suppressed if
> + * we never ran a test (due to an early bail, for example), and running any
> + * registered cleanup functions.
> + */
> +static void
> +finish(void)
> +{
> +    int success, primary;
> +    struct cleanup_func *current;
> +    unsigned long highest = testnum - 1;
> +    struct diag_file *file, *tmp;
> +
> +    /* Check for pending diag_file output. */
> +    check_diag_files();
> +
> +    /* Free the diag_files. */
> +    file = diag_files;
> +    while (file != NULL) {
> +        tmp = file;
> +        file = file->next;
> +        fclose(tmp->file);
> +        free(tmp->name);
> +        free(tmp->buffer);
> +        free(tmp);
> +    }
> +    diag_files = NULL;
> +
> +    /*
> +     * Determine whether all tests were successful, which is needed before
> +     * calling cleanup functions since we pass that fact to the functions.
> +     */
> +    if (_planned == 0 && _lazy)
> +        _planned = highest;
> +    success = (!_aborted && _planned == highest && _failed == 0);
> +
> +    /*
> +     * If there are any registered cleanup functions, we run those first.  We
> +     * always run them, even if we didn't run a test.  Don't do anything
> +     * except free the diag_files and call cleanup functions if we aren't the
> +     * primary process (the process in which plan or plan_lazy was called),
> +     * and tell the cleanup functions that fact.
> +     */
> +    primary = (_process == 0 || getpid() == _process);
> +    while (cleanup_funcs != NULL) {
> +        if (cleanup_funcs->func_with_data) {
> +            void *data = cleanup_funcs->data;
> +
> +            cleanup_funcs->func_with_data(success, primary, data);
> +        } else {
> +            cleanup_funcs->func(success, primary);
> +        }
> +        current = cleanup_funcs;
> +        cleanup_funcs = cleanup_funcs->next;
> +        free(current);
> +    }
> +    if (!primary)
> +        return;
> +
> +    /* Don't do anything further if we never planned a test. */
> +    if (_planned == 0)
> +        return;
> +
> +    /* If we're aborting due to bail, don't print summaries. */
> +    if (_aborted)
> +        return;
> +
> +    /* Print out the lazy plan if needed. */
> +    fflush(stderr);
> +    if (_lazy)
> +        printf("1..%lu\n", _planned);
> +
> +    /* Print out a summary of the results. */
> +    if (_planned > highest)
> +        diag("Looks like you planned %lu test%s but only ran %lu", _planned,
> +             (_planned > 1 ? "s" : ""), highest);
> +    else if (_planned < highest)
> +        diag("Looks like you planned %lu test%s but ran %lu extra", _planned,
> +             (_planned > 1 ? "s" : ""), highest - _planned);
> +    else if (_failed > 0)
> +        diag("Looks like you failed %lu test%s of %lu", _failed,
> +             (_failed > 1 ? "s" : ""), _planned);
> +    else if (_planned != 1)
> +        diag("All %lu tests successful or skipped", _planned);
> +    else
> +        diag("%lu test successful or skipped", _planned);
> +}
> +
> +
> +/*
> + * Initialize things.  Turns on line buffering on stdout and then prints out
> + * the number of tests in the test suite.  We intentionally don't check for
> + * pending diag_file output here, since it should really come after the plan.
> + */
> +void
> +plan(unsigned long count)
> +{
> +    if (setvbuf(stdout, NULL, _IOLBF, BUFSIZ) != 0)
> +        sysdiag("cannot set stdout to line buffered");
> +    fflush(stderr);
> +    printf("1..%lu\n", count);
> +    testnum = 1;
> +    _planned = count;
> +    _process = getpid();
> +    if (atexit(finish) != 0) {
> +        sysdiag("cannot register exit handler");
> +        diag("cleanups will not be run");
> +    }
> +}
> +
> +
> +/*
> + * Initialize things for lazy planning, where we'll automatically print out a
> + * plan at the end of the program.  Turns on line buffering on stdout as well.
> + */
> +void
> +plan_lazy(void)
> +{
> +    if (setvbuf(stdout, NULL, _IOLBF, BUFSIZ) != 0)
> +        sysdiag("cannot set stdout to line buffered");
> +    testnum = 1;
> +    _process = getpid();
> +    _lazy = 1;
> +    if (atexit(finish) != 0)
> +        sysbail("cannot register exit handler to display plan");
> +}
> +
> +
> +/*
> + * Skip the entire test suite and exits.  Should be called instead of plan(),
> + * not after it, since it prints out a special plan line.  Ignore diag_file
> + * output here, since it's not clear if it's allowed before the plan.
> + */
> +void
> +skip_all(const char *format, ...)
> +{
> +    fflush(stderr);
> +    printf("1..0 # skip");
> +    PRINT_DESC(" ", format);
> +    putchar('\n');
> +    exit(0);
> +}
> +
> +
> +/*
> + * Takes a boolean success value and assumes the test passes if that value
> + * is true and fails if that value is false.
> + */
> +int
> +ok(int success, const char *format, ...)
> +{
> +    fflush(stderr);
> +    check_diag_files();
> +    printf("%sok %lu", success ? "" : "not ", testnum++);
> +    if (!success)
> +        _failed++;
> +    PRINT_DESC(" - ", format);
> +    putchar('\n');
> +    return success;
> +}
> +
> +
> +/*
> + * Same as ok(), but takes the format arguments as a va_list.
> + */
> +int
> +okv(int success, const char *format, va_list args)
> +{
> +    fflush(stderr);
> +    check_diag_files();
> +    printf("%sok %lu", success ? "" : "not ", testnum++);
> +    if (!success)
> +        _failed++;
> +    if (format != NULL) {
> +        printf(" - ");
> +        vprintf(format, args);
> +    }
> +    putchar('\n');
> +    return success;
> +}
> +
> +
> +/*
> + * Skip a test.
> + */
> +void
> +skip(const char *reason, ...)
> +{
> +    fflush(stderr);
> +    check_diag_files();
> +    printf("ok %lu # skip", testnum++);
> +    PRINT_DESC(" ", reason);
> +    putchar('\n');
> +}
> +
> +
> +/*
> + * Report the same status on the next count tests.
> + */
> +int
> +ok_block(unsigned long count, int success, const char *format, ...)
> +{
> +    unsigned long i;
> +
> +    fflush(stderr);
> +    check_diag_files();
> +    for (i = 0; i < count; i++) {
> +        printf("%sok %lu", success ? "" : "not ", testnum++);
> +        if (!success)
> +            _failed++;
> +        PRINT_DESC(" - ", format);
> +        putchar('\n');
> +    }
> +    return success;
> +}
> +
> +
> +/*
> + * Skip the next count tests.
> + */
> +void
> +skip_block(unsigned long count, const char *reason, ...)
> +{
> +    unsigned long i;
> +
> +    fflush(stderr);
> +    check_diag_files();
> +    for (i = 0; i < count; i++) {
> +        printf("ok %lu # skip", testnum++);
> +        PRINT_DESC(" ", reason);
> +        putchar('\n');
> +    }
> +}
> +
> +
> +/*
> + * Takes two boolean values and requires the truth value of both match.
> + */
> +int
> +is_bool(int left, int right, const char *format, ...)
> +{
> +    int success;
> +
> +    fflush(stderr);
> +    check_diag_files();
> +    success = (!!left == !!right);
> +    if (success)
> +        printf("ok %lu", testnum++);
> +    else {
> +        diag(" left: %s", !!left ? "true" : "false");
> +        diag("right: %s", !!right ? "true" : "false");
> +        printf("not ok %lu", testnum++);
> +        _failed++;
> +    }
> +    PRINT_DESC(" - ", format);
> +    putchar('\n');
> +    return success;
> +}
> +
> +
> +/*
> + * Takes two integer values and requires they match.
> + */
> +int
> +is_int(long left, long right, const char *format, ...)
> +{
> +    int success;
> +
> +    fflush(stderr);
> +    check_diag_files();
> +    success = (left == right);
> +    if (success)
> +        printf("ok %lu", testnum++);
> +    else {
> +        diag(" left: %ld", left);
> +        diag("right: %ld", right);
> +        printf("not ok %lu", testnum++);
> +        _failed++;
> +    }
> +    PRINT_DESC(" - ", format);
> +    putchar('\n');
> +    return success;
> +}
> +
> +
> +/*
> + * Takes two strings and requires they match (using strcmp).  NULL arguments
> + * are permitted and handled correctly.
> + */
> +int
> +is_string(const char *left, const char *right, const char *format, ...)
> +{
> +    int success;
> +
> +    fflush(stderr);
> +    check_diag_files();
> +
> +    /* Compare the strings, being careful of NULL. */
> +    if (left == NULL)
> +        success = (right == NULL);
> +    else if (right == NULL)
> +        success = 0;
> +    else
> +        success = (strcmp(left, right) == 0);
> +
> +    /* Report the results. */
> +    if (success)
> +        printf("ok %lu", testnum++);
> +    else {
> +        diag(" left: %s", left == NULL ? "(null)" : left);
> +        diag("right: %s", right == NULL ? "(null)" : right);
> +        printf("not ok %lu", testnum++);
> +        _failed++;
> +    }
> +    PRINT_DESC(" - ", format);
> +    putchar('\n');
> +    return success;
> +}
> +
> +
> +/*
> + * Takes two unsigned longs and requires they match.  On failure, reports them
> + * in hex.
> + */
> +int
> +is_hex(unsigned long left, unsigned long right, const char *format, ...)
> +{
> +    int success;
> +
> +    fflush(stderr);
> +    check_diag_files();
> +    success = (left == right);
> +    if (success)
> +        printf("ok %lu", testnum++);
> +    else {
> +        diag(" left: %lx", (unsigned long) left);
> +        diag("right: %lx", (unsigned long) right);
> +        printf("not ok %lu", testnum++);
> +        _failed++;
> +    }
> +    PRINT_DESC(" - ", format);
> +    putchar('\n');
> +    return success;
> +}
> +
> +
> +/*
> + * Takes pointers to a regions of memory and requires that len bytes from each
> + * match.  Otherwise reports any bytes which didn't match.
> + */
> +int
> +is_blob(const void *left, const void *right, size_t len, const char *format,
> +        ...)
> +{
> +    int success;
> +    size_t i;
> +
> +    fflush(stderr);
> +    check_diag_files();
> +    success = (memcmp(left, right, len) == 0);
> +    if (success)
> +        printf("ok %lu", testnum++);
> +    else {
> +        const unsigned char *left_c = (const unsigned char *) left;
> +        const unsigned char *right_c = (const unsigned char *) right;
> +
> +        for (i = 0; i < len; i++) {
> +            if (left_c[i] != right_c[i])
> +                diag("offset %lu: left %02x, right %02x", (unsigned long) i,
> +                     left_c[i], right_c[i]);
> +        }
> +        printf("not ok %lu", testnum++);
> +        _failed++;
> +    }
> +    PRINT_DESC(" - ", format);
> +    putchar('\n');
> +    return success;
> +}
> +
> +
> +/*
> + * Bail out with an error.
> + */
> +void
> +bail(const char *format, ...)
> +{
> +    va_list args;
> +
> +    _aborted = 1;
> +    fflush(stderr);
> +    check_diag_files();
> +    fflush(stdout);
> +    printf("Bail out! ");
> +    va_start(args, format);
> +    vprintf(format, args);
> +    va_end(args);
> +    printf("\n");
> +    exit(255);
> +}
> +
> +
> +/*
> + * Bail out with an error, appending strerror(errno).
> + */
> +void
> +sysbail(const char *format, ...)
> +{
> +    va_list args;
> +    int oerrno = errno;
> +
> +    _aborted = 1;
> +    fflush(stderr);
> +    check_diag_files();
> +    fflush(stdout);
> +    printf("Bail out! ");
> +    va_start(args, format);
> +    vprintf(format, args);
> +    va_end(args);
> +    printf(": %s\n", strerror(oerrno));
> +    exit(255);
> +}
> +
> +
> +/*
> + * Report a diagnostic to stderr.  Always returns 1 to allow embedding in
> + * compound statements.
> + */
> +int
> +diag(const char *format, ...)
> +{
> +    va_list args;
> +
> +    fflush(stderr);
> +    check_diag_files();
> +    fflush(stdout);
> +    printf("# ");
> +    va_start(args, format);
> +    vprintf(format, args);
> +    va_end(args);
> +    printf("\n");
> +    return 1;
> +}
> +
> +
> +/*
> + * Report a diagnostic to stderr, appending strerror(errno).  Always returns 1
> + * to allow embedding in compound statements.
> + */
> +int
> +sysdiag(const char *format, ...)
> +{
> +    va_list args;
> +    int oerrno = errno;
> +
> +    fflush(stderr);
> +    check_diag_files();
> +    fflush(stdout);
> +    printf("# ");
> +    va_start(args, format);
> +    vprintf(format, args);
> +    va_end(args);
> +    printf(": %s\n", strerror(oerrno));
> +    return 1;
> +}
> +
> +
> +/*
> + * Register a new file for diag_file processing.
> + */
> +void
> +diag_file_add(const char *name)
> +{
> +    struct diag_file *file, *prev;
> +
> +    file = bcalloc_type(1, struct diag_file);
> +    file->name = bstrdup(name);
> +    file->file = fopen(file->name, "r");
> +    if (file->file == NULL)
> +        sysbail("cannot open %s", name);
> +    file->buffer = bcalloc_type(BUFSIZ, char);
> +    file->bufsize = BUFSIZ;
> +    if (diag_files == NULL)
> +        diag_files = file;
> +    else {
> +        for (prev = diag_files; prev->next != NULL; prev = prev->next)
> +            ;
> +        prev->next = file;
> +    }
> +}
> +
> +
> +/*
> + * Remove a file from diag_file processing.  If the file is not found, do
> + * nothing, since there are some situations where it can be removed twice
> + * (such as if it's removed from a cleanup function, since cleanup functions
> + * are called after freeing all the diag_files).
> + */
> +void
> +diag_file_remove(const char *name)
> +{
> +    struct diag_file *file;
> +    struct diag_file **prev = &diag_files;
> +
> +    for (file = diag_files; file != NULL; file = file->next) {
> +        if (strcmp(file->name, name) == 0) {
> +            *prev = file->next;
> +            fclose(file->file);
> +            free(file->name);
> +            free(file->buffer);
> +            free(file);
> +            return;
> +        }
> +        prev = &file->next;
> +    }
> +}
> +
> +
> +/*
> + * Allocate cleared memory, reporting a fatal error with bail on failure.
> + */
> +void *
> +bcalloc(size_t n, size_t size)
> +{
> +    void *p;
> +
> +    p = calloc(n, size);
> +    if (p == NULL)
> +        sysbail("failed to calloc %lu", (unsigned long) (n * size));
> +    return p;
> +}
> +
> +
> +/*
> + * Allocate memory, reporting a fatal error with bail on failure.
> + */
> +void *
> +bmalloc(size_t size)
> +{
> +    void *p;
> +
> +    p = malloc(size);
> +    if (p == NULL)
> +        sysbail("failed to malloc %lu", (unsigned long) size);
> +    return p;
> +}
> +
> +
> +/*
> + * Reallocate memory, reporting a fatal error with bail on failure.
> + */
> +void *
> +brealloc(void *p, size_t size)
> +{
> +    p = realloc(p, size);
> +    if (p == NULL)
> +        sysbail("failed to realloc %lu bytes", (unsigned long) size);
> +    return p;
> +}
> +
> +
> +/*
> + * The same as brealloc, but determine the size by multiplying an element
> + * count by a size, similar to calloc.  The multiplication is checked for
> + * integer overflow.
> + *
> + * We should technically use SIZE_MAX here for the overflow check, but
> + * SIZE_MAX is C99 and we're only assuming C89 + SUSv3, which does not
> + * guarantee that it exists.  They do guarantee that UINT_MAX exists, and we
> + * can assume that UINT_MAX <= SIZE_MAX.
> + *
> + * (In theory, C89 and C99 permit size_t to be smaller than unsigned int, but
> + * I disbelieve in the existence of such systems and they will have to cope
> + * without overflow checks.)
> + */
> +void *
> +breallocarray(void *p, size_t n, size_t size)
> +{
> +    if (n > 0 && UINT_MAX / n <= size)
> +        bail("reallocarray too large");
> +    if (n == 0)
> +        n = 1;
> +    p = realloc(p, n * size);
> +    if (p == NULL)
> +        sysbail("failed to realloc %lu bytes", (unsigned long) (n * size));
> +    return p;
> +}
> +
> +
> +/*
> + * Copy a string, reporting a fatal error with bail on failure.
> + */
> +char *
> +bstrdup(const char *s)
> +{
> +    char *p;
> +    size_t len;
> +
> +    len = strlen(s) + 1;
> +    p = (char *) malloc(len);
> +    if (p == NULL)
> +        sysbail("failed to strdup %lu bytes", (unsigned long) len);
> +    memcpy(p, s, len);
> +    return p;
> +}
> +
> +
> +/*
> + * Copy up to n characters of a string, reporting a fatal error with bail on
> + * failure.  Don't use the system strndup function, since it may not exist and
> + * the TAP library doesn't assume any portability support.
> + */
> +char *
> +bstrndup(const char *s, size_t n)
> +{
> +    const char *p;
> +    char *copy;
> +    size_t length;
> +
> +    /* Don't assume that the source string is nul-terminated. */
> +    for (p = s; (size_t) (p - s) < n && *p != '\0'; p++)
> +        ;
> +    length = (size_t) (p - s);
> +    copy = (char *) malloc(length + 1);
> +    if (copy == NULL)
> +        sysbail("failed to strndup %lu bytes", (unsigned long) length);
> +    memcpy(copy, s, length);
> +    copy[length] = '\0';
> +    return copy;
> +}
> +
> +
> +/*
> + * Locate a test file.  Given the partial path to a file, look under
> + * C_TAP_BUILD and then C_TAP_SOURCE for the file and return the full path to
> + * the file.  Returns NULL if the file doesn't exist.  A non-NULL return
> + * should be freed with test_file_path_free().
> + */
> +char *
> +test_file_path(const char *file)
> +{
> +    char *base;
> +    char *path = NULL;
> +    const char *envs[] = {"C_TAP_BUILD", "C_TAP_SOURCE", NULL};
> +    int i;
> +
> +    for (i = 0; envs[i] != NULL; i++) {
> +        base = getenv(envs[i]);
> +        if (base == NULL)
> +            continue;
> +        path = concat(base, "/", file, (const char *) 0);
> +        if (access(path, R_OK) == 0)
> +            break;
> +        free(path);
> +        path = NULL;
> +    }
> +    return path;
> +}
> +
> +
> +/*
> + * Free a path returned from test_file_path().  This function exists primarily
> + * for Windows, where memory must be freed from the same library domain that
> + * it was allocated from.
> + */
> +void
> +test_file_path_free(char *path)
> +{
> +    free(path);
> +}
> +
> +
> +/*
> + * Create a temporary directory, tmp, under C_TAP_BUILD if set and the current
> + * directory if it does not.  Returns the path to the temporary directory in
> + * newly allocated memory, and calls bail on any failure.  The return value
> + * should be freed with test_tmpdir_free.
> + *
> + * This function uses sprintf because it attempts to be independent of all
> + * other portability layers.  The use immediately after a memory allocation
> + * should be safe without using snprintf or strlcpy/strlcat.
> + */
> +char *
> +test_tmpdir(void)
> +{
> +    const char *build;
> +    char *path = NULL;
> +
> +    build = getenv("C_TAP_BUILD");
> +    if (build == NULL)
> +        build = ".";
> +    path = concat(build, "/tmp", (const char *) 0);
> +    if (access(path, X_OK) < 0)
> +        if (mkdir(path, 0777) < 0)
> +            sysbail("error creating temporary directory %s", path);
> +    return path;
> +}
> +
> +
> +/*
> + * Free a path returned from test_tmpdir() and attempt to remove the
> + * directory.  If we can't delete the directory, don't worry; something else
> + * that hasn't yet cleaned up may still be using it.
> + */
> +void
> +test_tmpdir_free(char *path)
> +{
> +    if (path != NULL)
> +        rmdir(path);
> +    free(path);
> +}
> +
> +static void
> +register_cleanup(test_cleanup_func func,
> +                 test_cleanup_func_with_data func_with_data, void *data)
> +{
> +    struct cleanup_func *cleanup, **last;
> +
> +    cleanup = bcalloc_type(1, struct cleanup_func);
> +    cleanup->func = func;
> +    cleanup->func_with_data = func_with_data;
> +    cleanup->data = data;
> +    cleanup->next = NULL;
> +    last = &cleanup_funcs;
> +    while (*last != NULL)
> +        last = &(*last)->next;
> +    *last = cleanup;
> +}
> +
> +/*
> + * Register a cleanup function that is called when testing ends.  All such
> + * registered functions will be run by finish.
> + */
> +void
> +test_cleanup_register(test_cleanup_func func)
> +{
> +    register_cleanup(func, NULL, NULL);
> +}
> +
> +/*
> + * Same as above, but also allows an opaque pointer to be passed to the cleanup
> + * function.
> + */
> +void
> +test_cleanup_register_with_data(test_cleanup_func_with_data func, void *data)
> +{
> +    register_cleanup(NULL, func, data);
> +}
> diff --git a/t/tap/basic.h b/t/tap/basic.h
> new file mode 100644
> index 0000000000..afea8cb210
> --- /dev/null
> +++ b/t/tap/basic.h
> @@ -0,0 +1,198 @@
> +/*
> + * Basic utility routines for the TAP protocol.
> + *
> + * This file is part of C TAP Harness.  The current version plus supporting
> + * documentation is at <https://www.eyrie.org/~eagle/software/c-tap-harness/>.
> + *
> + * Written by Russ Allbery <[email-masked]>
> + * Copyright 2009-2019, 2022 Russ Allbery <[email-masked]>
> + * Copyright 2001-2002, 2004-2008, 2011-2012, 2014
> + *     The Board of Trustees of the Leland Stanford Junior University
> + *
> + * Permission is hereby granted, free of charge, to any person obtaining a
> + * copy of this software and associated documentation files (the "Software"),
> + * to deal in the Software without restriction, including without limitation
> + * the rights to use, copy, modify, merge, publish, distribute, sublicense,
> + * and/or sell copies of the Software, and to permit persons to whom the
> + * Software is furnished to do so, subject to the following conditions:
> + *
> + * The above copyright notice and this permission notice shall be included in
> + * all copies or substantial portions of the Software.
> + *
> + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
> + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
> + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
> + * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
> + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
> + * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
> + * DEALINGS IN THE SOFTWARE.
> + *
> + * SPDX-License-Identifier: MIT
> + */
> +
> +#ifndef TAP_BASIC_H
> +#define TAP_BASIC_H 1
> +
> +#include <stdarg.h> /* va_list */
> +#include <stddef.h> /* size_t */
> +#include <stdlib.h> /* free */
> +#include <tap/macros.h>
> +
> +/*
> + * Used for iterating through arrays.  ARRAY_SIZE returns the number of
> + * elements in the array (useful for a < upper bound in a for loop) and
> + * ARRAY_END returns a pointer to the element past the end (ISO C99 makes it
> + * legal to refer to such a pointer as long as it's never dereferenced).
> + */
> +// #define ARRAY_SIZE(array) (sizeof(array) / sizeof((array)[0]))
> +// #define ARRAY_END(array)  (&(array)[ARRAY_SIZE(array)])
> +
> +BEGIN_DECLS
> +
> +/*
> + * The test count.  Always contains the number that will be used for the next
> + * test status.
> + */
> +extern unsigned long testnum;
> +
> +/* Print out the number of tests and set standard output to line buffered. */
> +void plan(unsigned long count);
> +
> +/*
> + * Prepare for lazy planning, in which the plan will be printed automatically
> + * at the end of the test program.
> + */
> +void plan_lazy(void);
> +
> +/* Skip the entire test suite.  Call instead of plan. */
> +void skip_all(const char *format, ...)
> +    __attribute__((__noreturn__, __format__(printf, 1, 2)));
> +
> +/*
> + * Basic reporting functions.  The okv() function is the same as ok() but
> + * takes the test description as a va_list to make it easier to reuse the
> + * reporting infrastructure when writing new tests.  ok() and okv() return the
> + * value of the success argument.
> + */
> +int ok(int success, const char *format, ...)
> +    __attribute__((__format__(printf, 2, 3)));
> +int okv(int success, const char *format, va_list args)
> +    __attribute__((__format__(printf, 2, 0)));
> +void skip(const char *reason, ...) __attribute__((__format__(printf, 1, 2)));
> +
> +/*
> + * Report the same status on, or skip, the next count tests.  ok_block()
> + * returns the value of the success argument.
> + */
> +int ok_block(unsigned long count, int success, const char *format, ...)
> +    __attribute__((__format__(printf, 3, 4)));
> +void skip_block(unsigned long count, const char *reason, ...)
> +    __attribute__((__format__(printf, 2, 3)));
> +
> +/*
> + * Compare two values.  Returns true if the test passes and false if it fails.
> + * is_bool takes an int since the bool type isn't fully portable yet, but
> + * interprets both arguments for their truth value, not for their numeric
> + * value.
> + */
> +int is_bool(int, int, const char *format, ...)
> +    __attribute__((__format__(printf, 3, 4)));
> +int is_int(long, long, const char *format, ...)
> +    __attribute__((__format__(printf, 3, 4)));
> +int is_string(const char *, const char *, const char *format, ...)
> +    __attribute__((__format__(printf, 3, 4)));
> +int is_hex(unsigned long, unsigned long, const char *format, ...)
> +    __attribute__((__format__(printf, 3, 4)));
> +int is_blob(const void *, const void *, size_t, const char *format, ...)
> +    __attribute__((__format__(printf, 4, 5)));
> +
> +/* Bail out with an error.  sysbail appends strerror(errno). */
> +void bail(const char *format, ...)
> +    __attribute__((__noreturn__, __nonnull__, __format__(printf, 1, 2)));
> +void sysbail(const char *format, ...)
> +    __attribute__((__noreturn__, __nonnull__, __format__(printf, 1, 2)));
> +
> +/* Report a diagnostic to stderr prefixed with #. */
> +int diag(const char *format, ...)
> +    __attribute__((__nonnull__, __format__(printf, 1, 2)));
> +int sysdiag(const char *format, ...)
> +    __attribute__((__nonnull__, __format__(printf, 1, 2)));
> +
> +/*
> + * Register or unregister a file that contains supplementary diagnostics.
> + * Before any other output, all registered files will be read, line by line,
> + * and each line will be reported as a diagnostic as if it were passed to
> + * diag().  Nul characters are not supported in these files and will result in
> + * truncated output.
> + */
> +void diag_file_add(const char *file) __attribute__((__nonnull__));
> +void diag_file_remove(const char *file) __attribute__((__nonnull__));
> +
> +/* Allocate memory, reporting a fatal error with bail on failure. */
> +void *bcalloc(size_t, size_t)
> +    __attribute__((__alloc_size__(1, 2), __malloc__(free),
> +                   __warn_unused_result__));
> +void *bmalloc(size_t) __attribute__((__alloc_size__(1), __malloc__(free),
> +                                     __warn_unused_result__));
> +void *breallocarray(void *, size_t, size_t)
> +    __attribute__((__alloc_size__(2, 3), __malloc__(free),
> +                   __warn_unused_result__));
> +void *brealloc(void *, size_t)
> +    __attribute__((__alloc_size__(2), __malloc__(free),
> +                   __warn_unused_result__));
> +char *bstrdup(const char *)
> +    __attribute__((__malloc__(free), __nonnull__, __warn_unused_result__));
> +char *bstrndup(const char *, size_t)
> +    __attribute__((__malloc__(free), __nonnull__, __warn_unused_result__));
> +
> +/*
> + * Macros that cast the return value from b* memory functions, making them
> + * usable in C++ code and providing some additional type safety.
> + */
> +#define bcalloc_type(n, type) ((type *) bcalloc((n), sizeof(type)))
> +#define breallocarray_type(p, n, type) \
> +    ((type *) breallocarray((p), (n), sizeof(type)))
> +
> +/*
> + * Find a test file under C_TAP_BUILD or C_TAP_SOURCE, returning the full
> + * path.  The returned path should be freed with test_file_path_free().
> + */
> +void test_file_path_free(char *path);
> +char *test_file_path(const char *file)
> +    __attribute__((__malloc__(test_file_path_free), __nonnull__,
> +                   __warn_unused_result__));
> +
> +/*
> + * Create a temporary directory relative to C_TAP_BUILD and return the path.
> + * The returned path should be freed with test_tmpdir_free().
> + */
> +void test_tmpdir_free(char *path);
> +char *test_tmpdir(void)
> +    __attribute__((__malloc__(test_tmpdir_free), __warn_unused_result__));
> +
> +/*
> + * Register a cleanup function that is called when testing ends.  All such
> + * registered functions will be run during atexit handling (and are therefore
> + * subject to all the same constraints and caveats as atexit functions).
> + *
> + * The function must return void and will be passed two arguments: an int that
> + * will be true if the test completed successfully and false otherwise, and an
> + * int that will be true if the cleanup function is run in the primary process
> + * (the one that called plan or plan_lazy) and false otherwise.  If
> + * test_cleanup_register_with_data is used instead, a generic pointer can be
> + * provided and will be passed to the cleanup function as a third argument.
> + *
> + * test_cleanup_register_with_data is the better API and should have been the
> + * only API.  test_cleanup_register was an API error preserved for backward
> + * cmpatibility.
> + */
> +typedef void (*test_cleanup_func)(int, int);
> +typedef void (*test_cleanup_func_with_data)(int, int, void *);
> +
> +void test_cleanup_register(test_cleanup_func) __attribute__((__nonnull__));
> +void test_cleanup_register_with_data(test_cleanup_func_with_data, void *)
> +    __attribute__((__nonnull__));
> +
> +END_DECLS
> +
> +#endif /* TAP_BASIC_H */
> diff --git a/t/tap/macros.h b/t/tap/macros.h
> new file mode 100644
> index 0000000000..0eabcb5847
> --- /dev/null
> +++ b/t/tap/macros.h
> @@ -0,0 +1,109 @@
> +/*
> + * Helpful macros for TAP header files.
> + *
> + * This is not, strictly speaking, related to TAP, but any TAP add-on is
> + * probably going to need these macros, so define them in one place so that
> + * everyone can pull them in.
> + *
> + * This file is part of C TAP Harness.  The current version plus supporting
> + * documentation is at <https://www.eyrie.org/~eagle/software/c-tap-harness/>.
> + *
> + * Copyright 2008, 2012-2013, 2015, 2022 Russ Allbery <[email-masked]>
> + *
> + * Permission is hereby granted, free of charge, to any person obtaining a
> + * copy of this software and associated documentation files (the "Software"),
> + * to deal in the Software without restriction, including without limitation
> + * the rights to use, copy, modify, merge, publish, distribute, sublicense,
> + * and/or sell copies of the Software, and to permit persons to whom the
> + * Software is furnished to do so, subject to the following conditions:
> + *
> + * The above copyright notice and this permission notice shall be included in
> + * all copies or substantial portions of the Software.
> + *
> + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
> + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
> + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
> + * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
> + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
> + * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
> + * DEALINGS IN THE SOFTWARE.
> + *
> + * SPDX-License-Identifier: MIT
> + */
> +
> +#ifndef TAP_MACROS_H
> +#define TAP_MACROS_H 1
> +
> +/*
> + * __attribute__ is available in gcc 2.5 and later, but only with gcc 2.7
> + * could you use the __format__ form of the attributes, which is what we use
> + * (to avoid confusion with other macros), and only with gcc 2.96 can you use
> + * the attribute __malloc__.  2.96 is very old, so don't bother trying to get
> + * the other attributes to work with GCC versions between 2.7 and 2.96.
> + */
> +#ifndef __attribute__
> +#    if __GNUC__ < 2 || (__GNUC__ == 2 && __GNUC_MINOR__ < 96)
> +#        define __attribute__(spec) /* empty */
> +#    endif
> +#endif
> +
> +/*
> + * We use __alloc_size__, but it was only available in fairly recent versions
> + * of GCC.  Suppress warnings about the unknown attribute if GCC is too old.
> + * We know that we're GCC at this point, so we can use the GCC variadic macro
> + * extension, which will still work with versions of GCC too old to have C99
> + * variadic macro support.
> + */
> +#if !defined(__attribute__) && !defined(__alloc_size__)
> +#    if defined(__GNUC__) && !defined(__clang__)
> +#        if __GNUC__ < 4 || (__GNUC__ == 4 && __GNUC_MINOR__ < 3)
> +#            define __alloc_size__(spec, args...) /* empty */
> +#        endif
> +#    endif
> +#endif
> +
> +/* Suppress __warn_unused_result__ if gcc is too old. */
> +#if !defined(__attribute__) && !defined(__warn_unused_result__)
> +#    if __GNUC__ < 3 || (__GNUC__ == 3 && __GNUC_MINOR__ < 4)
> +#        define __warn_unused_result__ /* empty */
> +#    endif
> +#endif
> +
> +/*
> + * Suppress the argument to __malloc__ in Clang (not supported in at least
> + * version 13) and GCC versions prior to 11.
> + */
> +#if !defined(__attribute__) && !defined(__malloc__)
> +#    if defined(__clang__) || __GNUC__ < 11
> +#        define __malloc__(dalloc) __malloc__
> +#    endif
> +#endif
> +
> +/*
> + * LLVM and Clang pretend to be GCC but don't support all of the __attribute__
> + * settings that GCC does.  For them, suppress warnings about unknown
> + * attributes on declarations.  This unfortunately will affect the entire
> + * compilation context, but there's no push and pop available.
> + */
> +#if !defined(__attribute__) && (defined(__llvm__) || defined(__clang__))
> +#    pragma GCC diagnostic ignored "-Wattributes"
> +#endif
> +
> +/* Used for unused parameters to silence gcc warnings. */
> +// #define UNUSED __attribute__((__unused__))
> +
> +/*
> + * BEGIN_DECLS is used at the beginning of declarations so that C++
> + * compilers don't mangle their names.  END_DECLS is used at the end.
> + */
> +#undef BEGIN_DECLS
> +#undef END_DECLS
> +#ifdef __cplusplus
> +#    define BEGIN_DECLS extern "C" {
> +#    define END_DECLS   }
> +#else
> +#    define BEGIN_DECLS /* empty */
> +#    define END_DECLS   /* empty */
> +#endif
> +
> +#endif /* TAP_MACROS_H */