diff options
Diffstat (limited to 'support/tst-support_capture_subprocess.c')
| -rw-r--r-- | support/tst-support_capture_subprocess.c | 188 |
1 files changed, 188 insertions, 0 deletions
diff --git a/support/tst-support_capture_subprocess.c b/support/tst-support_capture_subprocess.c new file mode 100644 index 0000000000..5672fba0f7 --- /dev/null +++ b/support/tst-support_capture_subprocess.c @@ -0,0 +1,188 @@ +/* Test capturing output from a subprocess. + Copyright (C) 2017 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, see + <http://www.gnu.org/licenses/>. */ + +#include <stdbool.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <support/capture_subprocess.h> +#include <support/check.h> +#include <support/support.h> +#include <sys/wait.h> +#include <unistd.h> + +/* Write one byte at *P to FD and advance *P. Do nothing if *P is + '\0'. */ +static void +transfer (const unsigned char **p, int fd) +{ + if (**p != '\0') + { + TEST_VERIFY (write (fd, *p, 1) == 1); + ++*p; + } +} + +/* Determine the order in which stdout and stderr are written. */ +enum write_mode { out_first, err_first, interleave, + write_mode_last = interleave }; + +/* Describe what to write in the subprocess. */ +struct test +{ + char *out; + char *err; + enum write_mode write_mode; + int signal; + int status; +}; + +/* For use with support_capture_subprocess. */ +static void +callback (void *closure) +{ + const struct test *test = closure; + bool mode_ok = false; + switch (test->write_mode) + { + case out_first: + TEST_VERIFY (fputs (test->out, stdout) >= 0); + TEST_VERIFY (fflush (stdout) == 0); + TEST_VERIFY (fputs (test->err, stderr) >= 0); + TEST_VERIFY (fflush (stderr) == 0); + mode_ok = true; + break; + case err_first: + TEST_VERIFY (fputs (test->err, stderr) >= 0); + TEST_VERIFY (fflush (stderr) == 0); + TEST_VERIFY (fputs (test->out, stdout) >= 0); + TEST_VERIFY (fflush (stdout) == 0); + mode_ok = true; + break; + case interleave: + { + const unsigned char *pout = (const unsigned char *) test->out; + const unsigned char *perr = (const unsigned char *) test->err; + do + { + transfer (&pout, STDOUT_FILENO); + transfer (&perr, STDERR_FILENO); + } + while (*pout != '\0' || *perr != '\0'); + } + mode_ok = true; + break; + } + TEST_VERIFY (mode_ok); + + if (test->signal != 0) + raise (test->signal); + exit (test->status); +} + +/* Create a heap-allocated random string of letters. */ +static char * +random_string (size_t length) +{ + char *result = xmalloc (length + 1); + for (size_t i = 0; i < length; ++i) + result[i] = 'a' + (rand () % 26); + result[length] = '\0'; + return result; +} + +/* Check that the specific stream from the captured subprocess matches + expectations. */ +static void +check_stream (const char *what, const struct xmemstream *stream, + const char *expected) +{ + if (strcmp (stream->buffer, expected) != 0) + { + support_record_failure (); + printf ("error: captured %s data incorrect\n" + " expected: %s\n" + " actual: %s\n", + what, expected, stream->buffer); + } + if (stream->length != strlen (expected)) + { + support_record_failure (); + printf ("error: captured %s data length incorrect\n" + " expected: %zu\n" + " actual: %zu\n", + what, strlen (expected), stream->length); + } +} + +static int +do_test (void) +{ + const int lengths[] = {0, 1, 17, 512, 20000, -1}; + + /* Test multiple combinations of support_capture_subprocess. + + length_idx_stdout: Index into the lengths array above, + controls how many bytes are written by the subprocess to + standard output. + length_idx_stderr: Same for standard error. + write_mode: How standard output and standard error writes are + ordered. + signal: Exit with no signal if zero, with SIGTERM if one. + status: Process exit status: 0 if zero, 3 if one. */ + for (int length_idx_stdout = 0; lengths[length_idx_stdout] >= 0; + ++length_idx_stdout) + for (int length_idx_stderr = 0; lengths[length_idx_stderr] >= 0; + ++length_idx_stderr) + for (int write_mode = 0; write_mode < write_mode_last; ++write_mode) + for (int signal = 0; signal < 2; ++signal) + for (int status = 0; status < 2; ++status) + { + struct test test = + { + .out = random_string (lengths[length_idx_stdout]), + .err = random_string (lengths[length_idx_stderr]), + .write_mode = write_mode, + .signal = signal * SIGTERM, /* 0 or SIGTERM. */ + .status = status * 3, /* 0 or 3. */ + }; + TEST_VERIFY (strlen (test.out) == lengths[length_idx_stdout]); + TEST_VERIFY (strlen (test.err) == lengths[length_idx_stderr]); + + struct support_capture_subprocess result + = support_capture_subprocess (callback, &test); + check_stream ("stdout", &result.out, test.out); + check_stream ("stderr", &result.err, test.err); + if (test.signal != 0) + { + TEST_VERIFY (WIFSIGNALED (result.status)); + TEST_VERIFY (WTERMSIG (result.status) == test.signal); + } + else + { + TEST_VERIFY (WIFEXITED (result.status)); + TEST_VERIFY (WEXITSTATUS (result.status) == test.status); + } + support_capture_subprocess_free (&result); + free (test.out); + free (test.err); + } + return 0; +} + +#include <support/test-driver.c> |