Line data Source code
1 : /*
2 : * exec.c
3 : *
4 : * execution functions
5 : *
6 : * Copyright (c) 2010-2025, PostgreSQL Global Development Group
7 : * src/bin/pg_upgrade/exec.c
8 : */
9 :
10 : #include "postgres_fe.h"
11 :
12 : #include <fcntl.h>
13 :
14 : #include "common/string.h"
15 : #include "fe_utils/version.h"
16 : #include "pg_upgrade.h"
17 :
18 : static void check_data_dir(ClusterInfo *cluster);
19 : static void check_bin_dir(ClusterInfo *cluster, bool check_versions);
20 : static void get_bin_version(ClusterInfo *cluster);
21 : static void check_exec(const char *dir, const char *program, bool check_version);
22 :
23 : #ifdef WIN32
24 : static int win32_check_directory_write_permissions(void);
25 : #endif
26 :
27 :
28 : /*
29 : * get_bin_version
30 : *
31 : * Fetch major version of binaries for cluster.
32 : */
33 : static void
34 68 : get_bin_version(ClusterInfo *cluster)
35 : {
36 : char cmd[MAXPGPATH],
37 : cmd_output[MAX_STRING];
38 : FILE *output;
39 : int rc;
40 68 : int v1 = 0,
41 68 : v2 = 0;
42 :
43 68 : snprintf(cmd, sizeof(cmd), "\"%s/pg_ctl\" --version", cluster->bindir);
44 68 : fflush(NULL);
45 :
46 136 : if ((output = popen(cmd, "r")) == NULL ||
47 68 : fgets(cmd_output, sizeof(cmd_output), output) == NULL)
48 0 : pg_fatal("could not get pg_ctl version data using %s: %m", cmd);
49 :
50 68 : rc = pclose(output);
51 68 : if (rc != 0)
52 0 : pg_fatal("could not get pg_ctl version data using %s: %s",
53 : cmd, wait_result_to_str(rc));
54 :
55 68 : if (sscanf(cmd_output, "%*s %*s %d.%d", &v1, &v2) < 1)
56 0 : pg_fatal("could not get pg_ctl version output from %s", cmd);
57 :
58 68 : if (v1 < 10)
59 : {
60 : /* old style, e.g. 9.6.1 */
61 0 : cluster->bin_version = v1 * 10000 + v2 * 100;
62 : }
63 : else
64 : {
65 : /* new style, e.g. 10.1 */
66 68 : cluster->bin_version = v1 * 10000;
67 : }
68 68 : }
69 :
70 :
71 : /*
72 : * exec_prog()
73 : * Execute an external program with stdout/stderr redirected, and report
74 : * errors
75 : *
76 : * Formats a command from the given argument list, logs it to the log file,
77 : * and attempts to execute that command. If the command executes
78 : * successfully, exec_prog() returns true.
79 : *
80 : * If the command fails, an error message is optionally written to the specified
81 : * log_file, and the program optionally exits.
82 : *
83 : * The code requires it be called first from the primary thread on Windows.
84 : */
85 : bool
86 542 : exec_prog(const char *log_filename, const char *opt_log_file,
87 : bool report_error, bool exit_on_error, const char *fmt,...)
88 : {
89 542 : int result = 0;
90 : int written;
91 : char log_file[MAXPGPATH];
92 :
93 : #define MAXCMDLEN (2 * MAXPGPATH)
94 : char cmd[MAXCMDLEN];
95 : FILE *log;
96 : va_list ap;
97 :
98 : #ifdef WIN32
99 : static DWORD mainThreadId = 0;
100 :
101 : /* We assume we are called from the primary thread first */
102 : if (mainThreadId == 0)
103 : mainThreadId = GetCurrentThreadId();
104 : #endif
105 :
106 542 : snprintf(log_file, MAXPGPATH, "%s/%s", log_opts.logdir, log_filename);
107 :
108 542 : written = 0;
109 542 : va_start(ap, fmt);
110 542 : written += vsnprintf(cmd + written, MAXCMDLEN - written, fmt, ap);
111 542 : va_end(ap);
112 542 : if (written >= MAXCMDLEN)
113 0 : pg_fatal("command too long");
114 542 : written += snprintf(cmd + written, MAXCMDLEN - written,
115 : " >> \"%s\" 2>&1", log_file);
116 542 : if (written >= MAXCMDLEN)
117 0 : pg_fatal("command too long");
118 :
119 542 : pg_log(PG_VERBOSE, "%s", cmd);
120 :
121 : #ifdef WIN32
122 :
123 : /*
124 : * For some reason, Windows issues a file-in-use error if we write data to
125 : * the log file from a non-primary thread just before we create a
126 : * subprocess that also writes to the same log file. One fix is to sleep
127 : * for 100ms. A cleaner fix is to write to the log file _after_ the
128 : * subprocess has completed, so we do this only when writing from a
129 : * non-primary thread. fflush(), running system() twice, and pre-creating
130 : * the file do not see to help.
131 : */
132 : if (mainThreadId != GetCurrentThreadId())
133 : {
134 : fflush(NULL);
135 : result = system(cmd);
136 : }
137 : #endif
138 :
139 542 : log = fopen(log_file, "a");
140 :
141 : #ifdef WIN32
142 : {
143 : /*
144 : * "pg_ctl -w stop" might have reported that the server has stopped
145 : * because the postmaster.pid file has been removed, but "pg_ctl -w
146 : * start" might still be in the process of closing and might still be
147 : * holding its stdout and -l log file descriptors open. Therefore,
148 : * try to open the log file a few more times.
149 : */
150 : int iter;
151 :
152 : for (iter = 0; iter < 4 && log == NULL; iter++)
153 : {
154 : pg_usleep(1000000); /* 1 sec */
155 : log = fopen(log_file, "a");
156 : }
157 : }
158 : #endif
159 :
160 542 : if (log == NULL)
161 0 : pg_fatal("could not open log file \"%s\": %m", log_file);
162 :
163 : #ifdef WIN32
164 : /* Are we printing "command:" before its output? */
165 : if (mainThreadId == GetCurrentThreadId())
166 : fprintf(log, "\n\n");
167 : #endif
168 542 : fprintf(log, "command: %s\n", cmd);
169 : #ifdef WIN32
170 : /* Are we printing "command:" after its output? */
171 : if (mainThreadId != GetCurrentThreadId())
172 : fprintf(log, "\n\n");
173 : #endif
174 :
175 : /*
176 : * In Windows, we must close the log file at this point so the file is not
177 : * open while the command is running, or we get a share violation.
178 : */
179 542 : fclose(log);
180 :
181 : #ifdef WIN32
182 : /* see comment above */
183 : if (mainThreadId == GetCurrentThreadId())
184 : #endif
185 : {
186 542 : fflush(NULL);
187 542 : result = system(cmd);
188 : }
189 :
190 542 : if (result != 0 && report_error)
191 : {
192 : /* we might be in on a progress status line, so go to the next line */
193 0 : report_status(PG_REPORT, "\n*failure*");
194 0 : fflush(stdout);
195 :
196 0 : pg_log(PG_VERBOSE, "There were problems executing \"%s\"", cmd);
197 0 : if (opt_log_file)
198 0 : pg_log(exit_on_error ? PG_FATAL : PG_REPORT,
199 : "Consult the last few lines of \"%s\" or \"%s\" for\n"
200 : "the probable cause of the failure.",
201 : log_file, opt_log_file);
202 : else
203 0 : pg_log(exit_on_error ? PG_FATAL : PG_REPORT,
204 : "Consult the last few lines of \"%s\" for\n"
205 : "the probable cause of the failure.",
206 : log_file);
207 : }
208 :
209 : #ifndef WIN32
210 :
211 : /*
212 : * We can't do this on Windows because it will keep the "pg_ctl start"
213 : * output filename open until the server stops, so we do the \n\n above on
214 : * that platform. We use a unique filename for "pg_ctl start" that is
215 : * never reused while the server is running, so it works fine. We could
216 : * log these commands to a third file, but that just adds complexity.
217 : */
218 542 : if ((log = fopen(log_file, "a")) == NULL)
219 0 : pg_fatal("could not write to log file \"%s\": %m", log_file);
220 542 : fprintf(log, "\n\n");
221 542 : fclose(log);
222 : #endif
223 :
224 542 : return result == 0;
225 : }
226 :
227 :
228 : /*
229 : * pid_lock_file_exists()
230 : *
231 : * Checks whether the postmaster.pid file exists.
232 : */
233 : bool
234 68 : pid_lock_file_exists(const char *datadir)
235 : {
236 : char path[MAXPGPATH];
237 : int fd;
238 :
239 68 : snprintf(path, sizeof(path), "%s/postmaster.pid", datadir);
240 :
241 68 : if ((fd = open(path, O_RDONLY, 0)) < 0)
242 : {
243 : /* ENOTDIR means we will throw a more useful error later */
244 68 : if (errno != ENOENT && errno != ENOTDIR)
245 0 : pg_fatal("could not open file \"%s\" for reading: %m", path);
246 :
247 68 : return false;
248 : }
249 :
250 0 : close(fd);
251 0 : return true;
252 : }
253 :
254 :
255 : /*
256 : * verify_directories()
257 : *
258 : * does all the hectic work of verifying directories and executables
259 : * of old and new server.
260 : *
261 : * NOTE: May update the values of all parameters
262 : */
263 : void
264 36 : verify_directories(void)
265 : {
266 : #ifndef WIN32
267 36 : if (access(".", R_OK | W_OK | X_OK) != 0)
268 : #else
269 : if (win32_check_directory_write_permissions() != 0)
270 : #endif
271 0 : pg_fatal("You must have read and write access in the current directory.");
272 :
273 36 : check_bin_dir(&old_cluster, false);
274 34 : check_data_dir(&old_cluster);
275 34 : check_bin_dir(&new_cluster, true);
276 34 : check_data_dir(&new_cluster);
277 34 : }
278 :
279 :
280 : #ifdef WIN32
281 : /*
282 : * win32_check_directory_write_permissions()
283 : *
284 : * access() on WIN32 can't check directory permissions, so we have to
285 : * optionally create, then delete a file to check.
286 : * http://msdn.microsoft.com/en-us/library/1w06ktdy%28v=vs.80%29.aspx
287 : */
288 : static int
289 : win32_check_directory_write_permissions(void)
290 : {
291 : int fd;
292 :
293 : /*
294 : * We open a file we would normally create anyway. We do this even in
295 : * 'check' mode, which isn't ideal, but this is the best we can do.
296 : */
297 : if ((fd = open(GLOBALS_DUMP_FILE, O_RDWR | O_CREAT, S_IRUSR | S_IWUSR)) < 0)
298 : return -1;
299 : close(fd);
300 :
301 : return unlink(GLOBALS_DUMP_FILE);
302 : }
303 : #endif
304 :
305 :
306 : /*
307 : * check_single_dir()
308 : *
309 : * Check for the presence of a single directory in PGDATA, and fail if
310 : * is it missing or not accessible.
311 : */
312 : static void
313 612 : check_single_dir(const char *pg_data, const char *subdir)
314 : {
315 : struct stat statBuf;
316 : char subDirName[MAXPGPATH];
317 :
318 612 : snprintf(subDirName, sizeof(subDirName), "%s%s%s", pg_data,
319 : /* Win32 can't stat() a directory with a trailing slash. */
320 612 : *subdir ? "/" : "",
321 : subdir);
322 :
323 612 : if (stat(subDirName, &statBuf) != 0)
324 0 : report_status(PG_FATAL, "check for \"%s\" failed: %m",
325 : subDirName);
326 612 : else if (!S_ISDIR(statBuf.st_mode))
327 0 : report_status(PG_FATAL, "\"%s\" is not a directory",
328 : subDirName);
329 612 : }
330 :
331 :
332 : /*
333 : * check_data_dir()
334 : *
335 : * This function validates the given cluster directory - we search for a
336 : * small set of subdirectories that we expect to find in a valid $PGDATA
337 : * directory. If any of the subdirectories are missing (or secured against
338 : * us) we display an error message and exit()
339 : *
340 : */
341 : static void
342 68 : check_data_dir(ClusterInfo *cluster)
343 : {
344 68 : const char *pg_data = cluster->pgdata;
345 :
346 : /* get the cluster version */
347 68 : cluster->major_version = get_pg_version(cluster->pgdata,
348 : &cluster->major_version_str);
349 68 : check_single_dir(pg_data, "");
350 68 : check_single_dir(pg_data, "base");
351 68 : check_single_dir(pg_data, "global");
352 68 : check_single_dir(pg_data, "pg_multixact");
353 68 : check_single_dir(pg_data, "pg_subtrans");
354 68 : check_single_dir(pg_data, PG_TBLSPC_DIR);
355 68 : check_single_dir(pg_data, "pg_twophase");
356 :
357 : /* pg_xlog has been renamed to pg_wal in v10 */
358 68 : if (GET_MAJOR_VERSION(cluster->major_version) <= 906)
359 0 : check_single_dir(pg_data, "pg_xlog");
360 : else
361 68 : check_single_dir(pg_data, "pg_wal");
362 :
363 : /* pg_clog has been renamed to pg_xact in v10 */
364 68 : if (GET_MAJOR_VERSION(cluster->major_version) <= 906)
365 0 : check_single_dir(pg_data, "pg_clog");
366 : else
367 68 : check_single_dir(pg_data, "pg_xact");
368 68 : }
369 :
370 :
371 : /*
372 : * check_bin_dir()
373 : *
374 : * This function searches for the executables that we expect to find
375 : * in the binaries directory. If we find that a required executable
376 : * is missing (or secured against us), we display an error message and
377 : * exit().
378 : *
379 : * If check_versions is true, then the versions of the binaries are checked
380 : * against the version of this pg_upgrade. This is for checking the target
381 : * bindir.
382 : */
383 : static void
384 70 : check_bin_dir(ClusterInfo *cluster, bool check_versions)
385 : {
386 : struct stat statBuf;
387 :
388 : /* check bindir */
389 70 : if (stat(cluster->bindir, &statBuf) != 0)
390 2 : report_status(PG_FATAL, "check for \"%s\" failed: %m",
391 : cluster->bindir);
392 68 : else if (!S_ISDIR(statBuf.st_mode))
393 0 : report_status(PG_FATAL, "\"%s\" is not a directory",
394 : cluster->bindir);
395 :
396 68 : check_exec(cluster->bindir, "postgres", check_versions);
397 68 : check_exec(cluster->bindir, "pg_controldata", check_versions);
398 68 : check_exec(cluster->bindir, "pg_ctl", check_versions);
399 :
400 : /*
401 : * Fetch the binary version after checking for the existence of pg_ctl.
402 : * This way we report a useful error if the pg_ctl binary used for version
403 : * fetching is missing/broken.
404 : */
405 68 : get_bin_version(cluster);
406 :
407 : /* pg_resetxlog has been renamed to pg_resetwal in version 10 */
408 68 : if (GET_MAJOR_VERSION(cluster->bin_version) <= 906)
409 0 : check_exec(cluster->bindir, "pg_resetxlog", check_versions);
410 : else
411 68 : check_exec(cluster->bindir, "pg_resetwal", check_versions);
412 :
413 68 : if (cluster == &new_cluster)
414 : {
415 : /*
416 : * These binaries are only needed for the target version. pg_dump and
417 : * pg_dumpall are used to dump the old cluster, but must be of the
418 : * target version.
419 : */
420 34 : check_exec(cluster->bindir, "initdb", check_versions);
421 34 : check_exec(cluster->bindir, "pg_dump", check_versions);
422 34 : check_exec(cluster->bindir, "pg_dumpall", check_versions);
423 34 : check_exec(cluster->bindir, "pg_restore", check_versions);
424 34 : check_exec(cluster->bindir, "psql", check_versions);
425 34 : check_exec(cluster->bindir, "vacuumdb", check_versions);
426 : }
427 68 : }
428 :
429 : static void
430 476 : check_exec(const char *dir, const char *program, bool check_version)
431 : {
432 : char path[MAXPGPATH];
433 : char *line;
434 : char cmd[MAXPGPATH];
435 : char versionstr[128];
436 :
437 476 : snprintf(path, sizeof(path), "%s/%s", dir, program);
438 :
439 476 : if (validate_exec(path) != 0)
440 0 : pg_fatal("check for \"%s\" failed: %m", path);
441 :
442 476 : snprintf(cmd, sizeof(cmd), "\"%s\" -V", path);
443 :
444 476 : if ((line = pipe_read_line(cmd)) == NULL)
445 0 : pg_fatal("check for \"%s\" failed: cannot execute",
446 : path);
447 :
448 476 : if (check_version)
449 : {
450 340 : pg_strip_crlf(line);
451 :
452 340 : snprintf(versionstr, sizeof(versionstr), "%s (PostgreSQL) " PG_VERSION, program);
453 :
454 340 : if (strcmp(line, versionstr) != 0)
455 0 : pg_fatal("check for \"%s\" failed: incorrect version: found \"%s\", expected \"%s\"",
456 : path, line, versionstr);
457 : }
458 :
459 476 : pg_free(line);
460 476 : }
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