aboutsummaryrefslogtreecommitdiff
path: root/support/tst-support_capture_subprocess.c
blob: c5926052c1358672f8ef3c244b181e8fcf454b9e (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
/* Test capturing output from a subprocess.
   Copyright (C) 2017-2022 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
   <https://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 <support/temp_file.h>
#include <sys/wait.h>
#include <unistd.h>
#include <paths.h>
#include <getopt.h>
#include <limits.h>
#include <errno.h>
#include <array_length.h>

/* Nonzero if the program gets called via 'exec'.  */
static int restart;

/* Hold the four initial argument used to respawn the process.  */
static char *initial_argv[5];

/* 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 };

static const char *
write_mode_to_str (enum write_mode mode)
{
  switch (mode)
    {
    case out_first:  return "out_first";
    case err_first:  return "err_first";
    case interleave: return "interleave";
    default:         return "write_mode_last";
    }
}

static enum write_mode
str_to_write_mode (const char *mode)
{
  if (strcmp (mode, "out_first") == 0)
    return out_first;
  else if (strcmp (mode, "err_first") == 0)
    return err_first;
  else if (strcmp (mode, "interleave") == 0)
    return interleave;
  return write_mode_last;
}

/* Describe what to write in the subprocess.  */
struct test
{
  char *out;
  char *err;
  enum write_mode write_mode;
  int signal;
  int status;
};

_Noreturn static void
test_common (const struct test *test)
{
  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);
}

static int
parse_int (const char *str)
{
  char *endptr;
  long int ret;
  errno = 0;
  ret = strtol (str, &endptr, 10);
  TEST_COMPARE (errno, 0);
  TEST_VERIFY (ret >= 0 && ret <= INT_MAX);
  return ret;
}

/* For use with support_capture_subprogram.  */
_Noreturn static void
handle_restart (char *out, char *err, const char *write_mode,
		const char *signal, const char *status)
{
  struct test test =
    {
      out,
      err,
      str_to_write_mode (write_mode),
      parse_int (signal),
      parse_int (status)
    };
  test_common (&test);
}

/* For use with support_capture_subprocess.  */
_Noreturn static void
callback (void *closure)
{
  const struct test *test = closure;
  test_common (test);
}

/* 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 struct support_capture_subprocess
do_subprocess (struct test *test)
{
  return support_capture_subprocess (callback, test);
}

static struct support_capture_subprocess
do_subprogram (const struct test *test)
{
  /* Three digits per byte plus null terminator.  */
  char signalstr[3 * sizeof(int) + 1];
  snprintf (signalstr, sizeof (signalstr), "%d", test->signal);
  char statusstr[3 * sizeof(int) + 1];
  snprintf (statusstr, sizeof (statusstr), "%d", test->status);

  int argc = 0;
  enum {
    /* 4 elements from initial_argv (path to ld.so, '--library-path', the
       path', and application name'), 2 for restart argument ('--direct',
       '--restart'), 5 arguments plus NULL.  */
    argv_size = 12
  };
  char *args[argv_size];

  for (char **arg = initial_argv; *arg != NULL; arg++)
    args[argc++] = *arg;

  args[argc++] = (char*) "--direct";
  args[argc++] = (char*) "--restart";

  args[argc++] = test->out;
  args[argc++] = test->err;
  args[argc++] = (char*) write_mode_to_str (test->write_mode);
  args[argc++] = signalstr;
  args[argc++] = statusstr;
  args[argc]   = NULL;
  TEST_VERIFY (argc < argv_size);

  return support_capture_subprogram (args[0], args);
}

enum test_type
{
  subprocess,
  subprogram,
};

static int
do_multiple_tests (enum test_type type)
{
  const int lengths[] = {0, 1, 17, 512, 20000, -1};

  /* Test multiple combinations of support_capture_sub{process,program}.

     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
		= type == subprocess ? do_subprocess (&test)
				     : do_subprogram (&test);

              check_stream ("stdout", &result.out, test.out);
              check_stream ("stderr", &result.err, test.err);

              /* Allowed output for support_capture_subprocess_check.  */
              int check_allow = 0;
              if (lengths[length_idx_stdout] > 0)
                check_allow |= sc_allow_stdout;
              if (lengths[length_idx_stderr] > 0)
                check_allow |= sc_allow_stderr;
              if (check_allow == 0)
                check_allow = sc_allow_none;

              if (test.signal != 0)
                {
                  TEST_VERIFY (WIFSIGNALED (result.status));
                  TEST_VERIFY (WTERMSIG (result.status) == test.signal);
                  support_capture_subprocess_check (&result, "signal",
                                                    -SIGTERM, check_allow);
                }
              else
                {
                  TEST_VERIFY (WIFEXITED (result.status));
                  TEST_VERIFY (WEXITSTATUS (result.status) == test.status);
                  support_capture_subprocess_check (&result, "exit",
                                                    test.status, check_allow);
                }
              support_capture_subprocess_free (&result);
              free (test.out);
              free (test.err);
            }
  return 0;
}

static int
do_test (int argc, char *argv[])
{
  /* We must have either:

     - one or four parameters if called initially:
       + argv[1]: path for ld.so        optional
       + argv[2]: "--library-path"      optional
       + argv[3]: the library path      optional
       + argv[4]: the application name

     - six parameters left if called through re-execution:
       + argv[1]: the application name
       + argv[2]: the stdout to print
       + argv[3]: the stderr to print
       + argv[4]: the write mode to use
       + argv[5]: the signal to issue
       + argv[6]: the exit status code to use

     * When built with --enable-hardcoded-path-in-tests or issued without
       using the loader directly.
  */

  if (argc != (restart ? 6 : 5) && argc != (restart ? 6 : 2))
    FAIL_EXIT1 ("wrong number of arguments (%d)", argc);

  if (restart)
    {
      handle_restart (argv[1],  /* stdout  */
		      argv[2],  /* stderr  */
		      argv[3],  /* write_mode  */
		      argv[4],  /* signal  */
		      argv[5]); /* status  */
    }

  initial_argv[0] = argv[1]; /* path for ld.so  */
  initial_argv[1] = argv[2]; /* "--library-path"  */
  initial_argv[2] = argv[3]; /* the library path  */
  initial_argv[3] = argv[4]; /* the application name  */
  initial_argv[4] = NULL;

  do_multiple_tests (subprocess);
  do_multiple_tests (subprogram);

  return 0;
}

#define CMDLINE_OPTIONS \
  { "restart", no_argument, &restart, 1 },
#define TEST_FUNCTION_ARGV do_test
#include <support/test-driver.c>