diff options
Diffstat (limited to 'support')
| -rw-r--r-- | support/Makefile | 4 | ||||
| -rw-r--r-- | support/capture_subprocess.h | 42 | ||||
| -rw-r--r-- | support/support_capture_subprocess.c | 108 | ||||
| -rw-r--r-- | support/tst-support_capture_subprocess.c | 188 | ||||
| -rw-r--r-- | support/xdup2.c | 28 | ||||
| -rw-r--r-- | support/xpipe.c | 28 | ||||
| -rw-r--r-- | support/xunistd.h | 2 |
7 files changed, 400 insertions, 0 deletions
diff --git a/support/Makefile b/support/Makefile index 38dbd832e9..3ce73a6c76 100644 --- a/support/Makefile +++ b/support/Makefile @@ -36,6 +36,7 @@ libsupport-routines = \ resolv_test \ set_fortify_handler \ support_become_root \ + support_capture_subprocess \ support_enter_network_namespace \ support_format_address_family \ support_format_addrinfo \ @@ -56,6 +57,7 @@ libsupport-routines = \ xcalloc \ xclose \ xconnect \ + xdup2 \ xfclose \ xfopen \ xfork \ @@ -65,6 +67,7 @@ libsupport-routines = \ xmemstream \ xmmap \ xmunmap \ + xpipe \ xpoll \ xpthread_attr_destroy \ xpthread_attr_init \ @@ -113,6 +116,7 @@ endif tests = \ README-testing \ tst-support-namespace \ + tst-support_capture_subprocess \ tst-support_format_dns_packet \ tst-support_record_failure \ diff --git a/support/capture_subprocess.h b/support/capture_subprocess.h new file mode 100644 index 0000000000..be5d34fbe2 --- /dev/null +++ b/support/capture_subprocess.h @@ -0,0 +1,42 @@ +/* Capture 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/>. */ + +#ifndef SUPPORT_CAPTURE_SUBPROCESS_H +#define SUPPORT_CAPTURE_SUBPROCESS_H + +#include <support/xmemstream.h> + +struct support_capture_subprocess +{ + struct xmemstream out; + struct xmemstream err; + int status; +}; + +/* Invoke CALLBACK (CLOSURE) in a subprocess and capture standard + output, standard error, and the exit status. The out.buffer and + err.buffer members in the result are null-terminated strings which + can be examined by the caller (out.out and err.out are NULL). */ +struct support_capture_subprocess support_capture_subprocess + (void (*callback) (void *), void *closure); + +/* Deallocate the subprocess data captured by + support_capture_subprocess. */ +void support_capture_subprocess_free (struct support_capture_subprocess *); + +#endif /* SUPPORT_CAPTURE_SUBPROCESS_H */ diff --git a/support/support_capture_subprocess.c b/support/support_capture_subprocess.c new file mode 100644 index 0000000000..030f124252 --- /dev/null +++ b/support/support_capture_subprocess.c @@ -0,0 +1,108 @@ +/* Capture 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 <support/capture_subprocess.h> + +#include <errno.h> +#include <stdlib.h> +#include <support/check.h> +#include <support/xunistd.h> +#include <support/xsocket.h> + +static void +transfer (const char *what, struct pollfd *pfd, struct xmemstream *stream) +{ + if (pfd->revents != 0) + { + char buf[1024]; + ssize_t ret = TEMP_FAILURE_RETRY (read (pfd->fd, buf, sizeof (buf))); + if (ret < 0) + { + support_record_failure (); + printf ("error: reading from subprocess %s: %m", what); + pfd->events = 0; + pfd->revents = 0; + } + else if (ret == 0) + { + /* EOF reached. Stop listening. */ + pfd->events = 0; + pfd->revents = 0; + } + else + /* Store the data just read. */ + TEST_VERIFY (fwrite (buf, ret, 1, stream->out) == 1); + } +} + +struct support_capture_subprocess +support_capture_subprocess (void (*callback) (void *), void *closure) +{ + struct support_capture_subprocess result; + xopen_memstream (&result.out); + xopen_memstream (&result.err); + + int stdout_pipe[2]; + xpipe (stdout_pipe); + int stderr_pipe[2]; + xpipe (stderr_pipe); + + TEST_VERIFY (fflush (stdout) == 0); + TEST_VERIFY (fflush (stderr) == 0); + + pid_t pid = xfork (); + if (pid == 0) + { + xclose (stdout_pipe[0]); + xclose (stderr_pipe[0]); + xdup2 (stdout_pipe[1], STDOUT_FILENO); + xdup2 (stderr_pipe[1], STDERR_FILENO); + callback (closure); + _exit (0); + } + xclose (stdout_pipe[1]); + xclose (stderr_pipe[1]); + + struct pollfd fds[2] = + { + { .fd = stdout_pipe[0], .events = POLLIN }, + { .fd = stderr_pipe[0], .events = POLLIN }, + }; + + do + { + xpoll (fds, 2, -1); + transfer ("stdout", &fds[0], &result.out); + transfer ("stderr", &fds[1], &result.err); + } + while (fds[0].events != 0 || fds[1].events != 0); + xclose (stdout_pipe[0]); + xclose (stderr_pipe[0]); + + xfclose_memstream (&result.out); + xfclose_memstream (&result.err); + xwaitpid (pid, &result.status, 0); + return result; +} + +void +support_capture_subprocess_free (struct support_capture_subprocess *p) +{ + free (p->out.buffer); + free (p->err.buffer); +} 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> diff --git a/support/xdup2.c b/support/xdup2.c new file mode 100644 index 0000000000..dc08c94518 --- /dev/null +++ b/support/xdup2.c @@ -0,0 +1,28 @@ +/* dup2 with error checking. + 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 <support/xunistd.h> + +#include <support/check.h> + +void +xdup2 (int from, int to) +{ + if (dup2 (from, to) < 0) + FAIL_EXIT1 ("dup2 (%d, %d): %m", from, to); +} diff --git a/support/xpipe.c b/support/xpipe.c new file mode 100644 index 0000000000..89a64a55c1 --- /dev/null +++ b/support/xpipe.c @@ -0,0 +1,28 @@ +/* pipe with error checking. + 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 <support/xunistd.h> + +#include <support/check.h> + +void +xpipe (int fds[2]) +{ + if (pipe (fds) < 0) + FAIL_EXIT1 ("pipe: %m"); +} diff --git a/support/xunistd.h b/support/xunistd.h index 258bab5c81..7c14bda7be 100644 --- a/support/xunistd.h +++ b/support/xunistd.h @@ -29,6 +29,8 @@ __BEGIN_DECLS pid_t xfork (void); pid_t xwaitpid (pid_t, int *status, int flags); +void xpipe (int[2]); +void xdup2 (int, int); /* Close the file descriptor. Ignore EINTR errors, but terminate the process on other errors. */ |