1 /* -*-pgsql-c-*- */
2 /*
3 *
4 * $Header$
5 *
6 * This file was imported from PostgreSQL source code.
7 * See below for the copyright and description.
8 *
9 * pgpool: a language independent connection pool server for PostgreSQL
10 * written by Tatsuo Ishii
11 *
12 * Portions Copyright (c) 2003-2020 PgPool Global Development Group
13 *
14 */
15 /*--------------------------------------------------------------------
16 * ps_status.c
17 *
18 * Routines to support changing the ps display of PostgreSQL backends
19 * to contain some useful information. Mechanism differs wildly across
20 * platforms.
21 *
22 * $PostgreSQL: pgsql/src/backend/utils/misc/ps_status.c,v 1.33 2006/10/04 00:30:04 momjian Exp $
23 *
24 * Copyright (c) 2000-2006, PostgreSQL Global Development Group
25 * various details abducted from various places
26 *--------------------------------------------------------------------
27 */
28
29 #include <unistd.h>
30 #ifdef HAVE_SYS_PSTAT_H
31 #include <sys/pstat.h> /* for HP-UX */
32 #endif
33 #ifdef HAVE_PS_STRINGS
34 #include <machine/vmparam.h> /* for old BSD */
35 #include <sys/exec.h>
36 #endif
37 #if defined(__darwin__)
38 #include <crt_externs.h>
39 #endif
40
41 #include "utils/ps_status.h"
42 #include "pool_type.h"
43 #include <stdlib.h>
44 #include <string.h>
45
46 extern char **environ;
47 bool update_process_title = true;
48 char remote_ps_data[NI_MAXHOST + NI_MAXSERV + 2]; /* used for set_ps_display */
49
50
51 /*
52 * Alternative ways of updating ps display:
53 *
54 * PS_USE_SETPROCTITLE
55 * use the function setproctitle(const char *, ...)
56 * (newer BSD systems)
57 * PS_USE_PSTAT
58 * use the pstat(PSTAT_SETCMD, )
59 * (HPUX)
60 * PS_USE_PS_STRINGS
61 * assign PS_STRINGS->ps_argvstr = "string"
62 * (some BSD systems)
63 * PS_USE_CHANGE_ARGV
64 * assign argv[0] = "string"
65 * (some other BSD systems)
66 * PS_USE_CLOBBER_ARGV
67 * write over the argv and environment area
68 * (most SysV-like systems)
69 * PS_USE_WIN32
70 * push the string out as the name of a Windows event
71 * PS_USE_NONE
72 * don't update ps display
73 * (This is the default, as it is safest.)
74 */
75 #if defined(HAVE_SETPROCTITLE)
76 #define PS_USE_SETPROCTITLE
77 #elif defined(HAVE_PSTAT) && defined(PSTAT_SETCMD)
78 #define PS_USE_PSTAT
79 #elif defined(HAVE_PS_STRINGS)
80 #define PS_USE_PS_STRINGS
81 #elif (defined(BSD) || defined(__bsdi__) || defined(__hurd__)) && !defined(__darwin__)
82 #define PS_USE_CHANGE_ARGV
83 #elif defined(__linux__) || defined(_AIX) || defined(__sgi) || (defined(sun) && !defined(BSD)) || defined(ultrix) || defined(__ksr__) || defined(__osf__) || defined(__svr4__) || defined(__svr5__) || defined(__darwin__)
84 #define PS_USE_CLOBBER_ARGV
85 #elif defined(WIN32)
86 #define PS_USE_WIN32
87 #else
88 #define PS_USE_NONE
89 #endif
90
91
92 /* Different systems want the buffer padded differently */
93 #if defined(_AIX) || defined(__linux__) || defined(__svr4__)
94 #define PS_PADDING '\0'
95 #else
96 #define PS_PADDING ' '
97 #endif
98
99
100 #ifndef PS_USE_CLOBBER_ARGV
101 /* all but one options need a buffer to write their ps line in */
102 #define PS_BUFFER_SIZE 256
103 static char ps_buffer[PS_BUFFER_SIZE];
104 static const size_t ps_buffer_size = PS_BUFFER_SIZE;
105 #else /* PS_USE_CLOBBER_ARGV */
106 static char *ps_buffer; /* will point to argv area */
107 static size_t ps_buffer_size; /* space determined at run time */
108 #endif /* PS_USE_CLOBBER_ARGV */
109
110 static size_t ps_buffer_fixed_size; /* size of the constant prefix */
111
112 /* save the original argv[] location here */
113 static int save_argc;
114 static char **save_argv;
115
116
117 /*
118 * Call this early in startup to save the original argc/argv values.
119 * If needed, we make a copy of the original argv[] array to preserve it
120 * from being clobbered by subsequent ps_display actions.
121 *
122 * (The original argv[] will not be overwritten by this routine, but may be
123 * overwritten during init_ps_display. Also, the physical location of the
124 * environment strings may be moved, so this should be called before any code
125 * that might try to hang onto a getenv() result.)
126 */
127 char **
save_ps_display_args(int argc,char ** argv)128 save_ps_display_args(int argc, char **argv)
129 {
130 save_argc = argc;
131 save_argv = argv;
132
133 #if defined(PS_USE_CLOBBER_ARGV)
134
135 /*
136 * If we're going to overwrite the argv area, count the available space.
137 * Also move the environment to make additional room.
138 */
139 {
140 char *end_of_area = NULL;
141 char **new_environ;
142 int i;
143
144 /*
145 * check for contiguous argv strings
146 */
147 for (i = 0; i < argc; i++)
148 {
149 if (i == 0 || end_of_area + 1 == argv[i])
150 end_of_area = argv[i] + strlen(argv[i]);
151 }
152
153 if (end_of_area == NULL) /* probably can't happen? */
154 {
155 ps_buffer = NULL;
156 ps_buffer_size = 0;
157 return argv;
158 }
159
160 /*
161 * check for contiguous environ strings following argv
162 */
163 for (i = 0; environ[i] != NULL; i++)
164 {
165 if (end_of_area + 1 == environ[i])
166 end_of_area = environ[i] + strlen(environ[i]);
167 }
168
169 ps_buffer = argv[0];
170 ps_buffer_size = end_of_area - argv[0];
171
172 /*
173 * move the environment out of the way
174 */
175 new_environ = (char **) malloc((i + 1) * sizeof(char *));
176 for (i = 0; environ[i] != NULL; i++)
177 new_environ[i] = strdup(environ[i]);
178 new_environ[i] = NULL;
179 environ = new_environ;
180 }
181 #endif /* PS_USE_CLOBBER_ARGV */
182
183 #if defined(PS_USE_CHANGE_ARGV) || defined(PS_USE_CLOBBER_ARGV)
184
185 /*
186 * If we're going to change the original argv[] then make a copy for
187 * argument parsing purposes.
188 *
189 * (NB: do NOT think to remove the copying of argv[], even though
190 * postmaster.c finishes looking at argv[] long before we ever consider
191 * changing the ps display. On some platforms, getopt() keeps pointers
192 * into the argv array, and will get horribly confused when it is
193 * re-called to analyze a subprocess' argument string if the argv storage
194 * has been clobbered meanwhile. Other platforms have other dependencies
195 * on argv[].
196 */
197 {
198 char **new_argv;
199 int i;
200
201 new_argv = (char **) malloc((argc + 1) * sizeof(char *));
202 for (i = 0; i < argc; i++)
203 new_argv[i] = strdup(argv[i]);
204 new_argv[argc] = NULL;
205
206 #if defined(__darwin__)
207
208 /*
209 * Darwin (and perhaps other NeXT-derived platforms?) has a static
210 * copy of the argv pointer, which we may fix like so:
211 */
212 *_NSGetArgv() = new_argv;
213 #endif
214
215 argv = new_argv;
216 }
217 #endif /* PS_USE_CHANGE_ARGV or PS_USE_CLOBBER_ARGV */
218
219 return argv;
220 }
221
222 /*
223 * Call this once during subprocess startup to set the identification
224 * values. At this point, the original argv[] array may be overwritten.
225 */
226 void
init_ps_display(const char * username,const char * dbname,const char * host_info,const char * initial_str)227 init_ps_display(const char *username, const char *dbname,
228 const char *host_info, const char *initial_str)
229 {
230 #ifndef PS_USE_NONE
231 /* no ps display if you didn't call save_ps_display_args() */
232 if (!save_argv)
233 return;
234 #ifdef PS_USE_CLOBBER_ARGV
235 /* If ps_buffer is a pointer, it might still be null */
236 if (!ps_buffer)
237 return;
238 #endif
239
240 /*
241 * Overwrite argv[] to point at appropriate space, if needed
242 */
243
244 #ifdef PS_USE_CHANGE_ARGV
245 save_argv[0] = ps_buffer;
246 save_argv[1] = NULL;
247 #endif /* PS_USE_CHANGE_ARGV */
248
249 #ifdef PS_USE_CLOBBER_ARGV
250 {
251 int i;
252
253 /* make extra argv slots point at end_of_area (a NUL) */
254 for (i = 1; i < save_argc; i++)
255 save_argv[i] = ps_buffer + ps_buffer_size;
256 }
257 #endif /* PS_USE_CLOBBER_ARGV */
258
259 /*
260 * Make fixed prefix of ps display.
261 */
262
263 #ifdef PS_USE_SETPROCTITLE
264
265 /*
266 * apparently setproctitle() already adds a `progname: ' prefix to the ps
267 * line
268 */
269 snprintf(ps_buffer, ps_buffer_size, "");
270 #else
271 snprintf(ps_buffer, ps_buffer_size,
272 "pgpool: ");
273 #endif
274
275 ps_buffer_fixed_size = strlen(ps_buffer);
276
277 set_ps_display(initial_str, true);
278 #endif /* not PS_USE_NONE */
279 }
280
281
282
283 /*
284 * Call this to update the ps status display to a fixed prefix plus an
285 * indication of what you're currently doing passed in the argument.
286 */
287 void
set_ps_display(const char * activity,bool force)288 set_ps_display(const char *activity, bool force)
289 {
290
291 if (!force && !update_process_title)
292 return;
293
294 #ifndef PS_USE_NONE
295
296 #ifdef PS_USE_CLOBBER_ARGV
297 /* If ps_buffer is a pointer, it might still be null */
298 if (!ps_buffer)
299 return;
300 #endif
301
302 /* Update ps_buffer to contain both fixed part and activity */
303 strlcpy(ps_buffer + ps_buffer_fixed_size, activity,
304 ps_buffer_size - ps_buffer_fixed_size);
305
306 /* Transmit new setting to kernel, if necessary */
307
308 #ifdef PS_USE_SETPROCTITLE
309 setproctitle("%s", ps_buffer);
310 #endif
311
312 #ifdef PS_USE_PSTAT
313 {
314 union pstun pst;
315
316 pst.pst_command = ps_buffer;
317 pstat(PSTAT_SETCMD, pst, strlen(ps_buffer), 0, 0);
318 }
319 #endif /* PS_USE_PSTAT */
320
321 #ifdef PS_USE_PS_STRINGS
322 PS_STRINGS->ps_nargvstr = 1;
323 PS_STRINGS->ps_argvstr = ps_buffer;
324 #endif /* PS_USE_PS_STRINGS */
325
326 #ifdef PS_USE_CLOBBER_ARGV
327 {
328 int buflen;
329
330 /* pad unused memory */
331 buflen = strlen(ps_buffer);
332 memset(ps_buffer + buflen, PS_PADDING, ps_buffer_size - buflen);
333 }
334 #endif /* PS_USE_CLOBBER_ARGV */
335
336 #ifdef PS_USE_WIN32
337 {
338 /*
339 * Win32 does not support showing any changed arguments. To make it at
340 * all possible to track which backend is doing what, we create a
341 * named object that can be viewed with for example Process Explorer.
342 */
343 static HANDLE ident_handle = INVALID_HANDLE_VALUE;
344 char name[PS_BUFFER_SIZE + 32];
345
346 if (ident_handle != INVALID_HANDLE_VALUE)
347 CloseHandle(ident_handle);
348
349 sprintf(name, "pgident: %s", ps_buffer);
350
351 ident_handle = CreateEvent(NULL, TRUE, FALSE, name);
352 }
353 #endif /* PS_USE_WIN32 */
354
355 #endif /* not PS_USE_NONE */
356 }
357
358
359 /*
360 * Returns what's currently in the ps display, in case someone needs
361 * it. Note that only the activity part is returned. On some platforms
362 * the string will not be null-terminated, so return the effective
363 * length into *displen.
364 */
365 const char *
get_ps_display(int * displen)366 get_ps_display(int *displen)
367 {
368 #ifdef PS_USE_CLOBBER_ARGV
369 size_t offset;
370
371 /* If ps_buffer is a pointer, it might still be null */
372 if (!ps_buffer)
373 {
374 *displen = 0;
375 return "";
376 }
377
378 /* Remove any trailing spaces to offset the effect of PS_PADDING */
379 offset = ps_buffer_size;
380 while (offset > ps_buffer_fixed_size && ps_buffer[offset - 1] == PS_PADDING)
381 offset--;
382
383 *displen = offset - ps_buffer_fixed_size;
384 #else
385 *displen = strlen(ps_buffer + ps_buffer_fixed_size);
386 #endif
387
388 return ps_buffer + ps_buffer_fixed_size;
389 }
390
391 /*
392 * Show ps idle status
393 */
394 void
pool_ps_idle_display(POOL_CONNECTION_POOL * backend)395 pool_ps_idle_display(POOL_CONNECTION_POOL * backend)
396 {
397 StartupPacket *sp;
398 char psbuf[1024];
399
400 sp = MAIN_CONNECTION(backend)->sp;
401 if (MAIN(backend)->tstate == 'T')
402 snprintf(psbuf, sizeof(psbuf), "%s %s %s idle in transaction",
403 sp->user, sp->database, remote_ps_data);
404 else
405 snprintf(psbuf, sizeof(psbuf), "%s %s %s idle",
406 sp->user, sp->database, remote_ps_data);
407 set_ps_display(psbuf, false);
408 }
409