PostgreSQL Source Code  git master
server.c
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1 /*
2  * server.c
3  *
4  * database server functions
5  *
6  * Copyright (c) 2010-2019, PostgreSQL Global Development Group
7  * src/bin/pg_upgrade/server.c
8  */
9 
10 #include "postgres_fe.h"
11 
12 #include "fe_utils/connect.h"
13 #include "fe_utils/string_utils.h"
14 #include "pg_upgrade.h"
15 
16 static PGconn *get_db_conn(ClusterInfo *cluster, const char *db_name);
17 
18 
19 /*
20  * connectToServer()
21  *
22  * Connects to the desired database on the designated server.
23  * If the connection attempt fails, this function logs an error
24  * message and calls exit() to kill the program.
25  */
26 PGconn *
27 connectToServer(ClusterInfo *cluster, const char *db_name)
28 {
29  PGconn *conn = get_db_conn(cluster, db_name);
30 
31  if (conn == NULL || PQstatus(conn) != CONNECTION_OK)
32  {
33  pg_log(PG_REPORT, "connection to database failed: %s",
34  PQerrorMessage(conn));
35 
36  if (conn)
37  PQfinish(conn);
38 
39  printf(_("Failure, exiting\n"));
40  exit(1);
41  }
42 
44 
45  return conn;
46 }
47 
48 
49 /*
50  * get_db_conn()
51  *
52  * get database connection, using named database + standard params for cluster
53  */
54 static PGconn *
55 get_db_conn(ClusterInfo *cluster, const char *db_name)
56 {
57  PQExpBufferData conn_opts;
58  PGconn *conn;
59 
60  /* Build connection string with proper quoting */
61  initPQExpBuffer(&conn_opts);
62  appendPQExpBufferStr(&conn_opts, "dbname=");
63  appendConnStrVal(&conn_opts, db_name);
64  appendPQExpBufferStr(&conn_opts, " user=");
65  appendConnStrVal(&conn_opts, os_info.user);
66  appendPQExpBuffer(&conn_opts, " port=%d", cluster->port);
67  if (cluster->sockdir)
68  {
69  appendPQExpBufferStr(&conn_opts, " host=");
70  appendConnStrVal(&conn_opts, cluster->sockdir);
71  }
72 
73  conn = PQconnectdb(conn_opts.data);
74  termPQExpBuffer(&conn_opts);
75  return conn;
76 }
77 
78 
79 /*
80  * cluster_conn_opts()
81  *
82  * Return standard command-line options for connecting to this cluster when
83  * using psql, pg_dump, etc. Ideally this would match what get_db_conn()
84  * sets, but the utilities we need aren't very consistent about the treatment
85  * of database name options, so we leave that out.
86  *
87  * Result is valid until the next call to this function.
88  */
89 char *
91 {
92  static PQExpBuffer buf;
93 
94  if (buf == NULL)
95  buf = createPQExpBuffer();
96  else
97  resetPQExpBuffer(buf);
98 
99  if (cluster->sockdir)
100  {
101  appendPQExpBufferStr(buf, "--host ");
102  appendShellString(buf, cluster->sockdir);
103  appendPQExpBufferChar(buf, ' ');
104  }
105  appendPQExpBuffer(buf, "--port %d --username ", cluster->port);
107 
108  return buf->data;
109 }
110 
111 
112 /*
113  * executeQueryOrDie()
114  *
115  * Formats a query string from the given arguments and executes the
116  * resulting query. If the query fails, this function logs an error
117  * message and calls exit() to kill the program.
118  */
119 PGresult *
120 executeQueryOrDie(PGconn *conn, const char *fmt,...)
121 {
122  static char query[QUERY_ALLOC];
123  va_list args;
124  PGresult *result;
126 
127  va_start(args, fmt);
128  vsnprintf(query, sizeof(query), fmt, args);
129  va_end(args);
130 
131  pg_log(PG_VERBOSE, "executing: %s\n", query);
132  result = PQexec(conn, query);
133  status = PQresultStatus(result);
134 
135  if ((status != PGRES_TUPLES_OK) && (status != PGRES_COMMAND_OK))
136  {
137  pg_log(PG_REPORT, "SQL command failed\n%s\n%s", query,
138  PQerrorMessage(conn));
139  PQclear(result);
140  PQfinish(conn);
141  printf(_("Failure, exiting\n"));
142  exit(1);
143  }
144  else
145  return result;
146 }
147 
148 
149 /*
150  * get_major_server_version()
151  *
152  * gets the version (in unsigned int form) for the given datadir. Assumes
153  * that datadir is an absolute path to a valid pgdata directory. The version
154  * is retrieved by reading the PG_VERSION file.
155  */
156 uint32
158 {
159  FILE *version_fd;
160  char ver_filename[MAXPGPATH];
161  int v1 = 0,
162  v2 = 0;
163 
164  snprintf(ver_filename, sizeof(ver_filename), "%s/PG_VERSION",
165  cluster->pgdata);
166  if ((version_fd = fopen(ver_filename, "r")) == NULL)
167  pg_fatal("could not open version file: %s\n", ver_filename);
168 
169  if (fscanf(version_fd, "%63s", cluster->major_version_str) == 0 ||
170  sscanf(cluster->major_version_str, "%d.%d", &v1, &v2) < 1)
171  pg_fatal("could not parse PG_VERSION file from %s\n", cluster->pgdata);
172 
173  fclose(version_fd);
174 
175  if (v1 < 10)
176  {
177  /* old style, e.g. 9.6.1 */
178  return v1 * 10000 + v2 * 100;
179  }
180  else
181  {
182  /* new style, e.g. 10.1 */
183  return v1 * 10000;
184  }
185 }
186 
187 
188 static void
190 {
191  stop_postmaster(true);
192 }
193 
194 
195 bool
196 start_postmaster(ClusterInfo *cluster, bool report_and_exit_on_error)
197 {
198  char cmd[MAXPGPATH * 4 + 1000];
199  PGconn *conn;
200  bool pg_ctl_return = false;
201  char socket_string[MAXPGPATH + 200];
202 
203  static bool exit_hook_registered = false;
204 
205  if (!exit_hook_registered)
206  {
207  atexit(stop_postmaster_atexit);
208  exit_hook_registered = true;
209  }
210 
211  socket_string[0] = '\0';
212 
213 #ifdef HAVE_UNIX_SOCKETS
214  /* prevent TCP/IP connections, restrict socket access */
215  strcat(socket_string,
216  " -c listen_addresses='' -c unix_socket_permissions=0700");
217 
218  /* Have a sockdir? Tell the postmaster. */
219  if (cluster->sockdir)
220  snprintf(socket_string + strlen(socket_string),
221  sizeof(socket_string) - strlen(socket_string),
222  " -c %s='%s'",
223  (GET_MAJOR_VERSION(cluster->major_version) < 903) ?
224  "unix_socket_directory" : "unix_socket_directories",
225  cluster->sockdir);
226 #endif
227 
228  /*
229  * Since PG 9.1, we have used -b to disable autovacuum. For earlier
230  * releases, setting autovacuum=off disables cleanup vacuum and analyze,
231  * but freeze vacuums can still happen, so we set
232  * autovacuum_freeze_max_age to its maximum.
233  * (autovacuum_multixact_freeze_max_age was introduced after 9.1, so there
234  * is no need to set that.) We assume all datfrozenxid and relfrozenxid
235  * values are less than a gap of 2000000000 from the current xid counter,
236  * so autovacuum will not touch them.
237  *
238  * Turn off durability requirements to improve object creation speed, and
239  * we only modify the new cluster, so only use it there. If there is a
240  * crash, the new cluster has to be recreated anyway. fsync=off is a big
241  * win on ext4.
242  */
243  snprintf(cmd, sizeof(cmd),
244  "\"%s/pg_ctl\" -w -l \"%s\" -D \"%s\" -o \"-p %d%s%s %s%s\" start",
245  cluster->bindir, SERVER_LOG_FILE, cluster->pgconfig, cluster->port,
246  (cluster->controldata.cat_ver >=
248  " -c autovacuum=off -c autovacuum_freeze_max_age=2000000000",
249  (cluster == &new_cluster) ?
250  " -c synchronous_commit=off -c fsync=off -c full_page_writes=off" : "",
251  cluster->pgopts ? cluster->pgopts : "", socket_string);
252 
253  /*
254  * Don't throw an error right away, let connecting throw the error because
255  * it might supply a reason for the failure.
256  */
257  pg_ctl_return = exec_prog(SERVER_START_LOG_FILE,
258  /* pass both file names if they differ */
259  (strcmp(SERVER_LOG_FILE,
260  SERVER_START_LOG_FILE) != 0) ?
261  SERVER_LOG_FILE : NULL,
262  report_and_exit_on_error, false,
263  "%s", cmd);
264 
265  /* Did it fail and we are just testing if the server could be started? */
266  if (!pg_ctl_return && !report_and_exit_on_error)
267  return false;
268 
269  /*
270  * We set this here to make sure atexit() shuts down the server, but only
271  * if we started the server successfully. We do it before checking for
272  * connectivity in case the server started but there is a connectivity
273  * failure. If pg_ctl did not return success, we will exit below.
274  *
275  * Pre-9.1 servers do not have PQping(), so we could be leaving the server
276  * running if authentication was misconfigured, so someday we might went
277  * to be more aggressive about doing server shutdowns even if pg_ctl
278  * fails, but now (2013-08-14) it seems prudent to be cautious. We don't
279  * want to shutdown a server that might have been accidentally started
280  * during the upgrade.
281  */
282  if (pg_ctl_return)
284 
285  /*
286  * pg_ctl -w might have failed because the server couldn't be started, or
287  * there might have been a connection problem in _checking_ if the server
288  * has started. Therefore, even if pg_ctl failed, we continue and test
289  * for connectivity in case we get a connection reason for the failure.
290  */
291  if ((conn = get_db_conn(cluster, "template1")) == NULL ||
292  PQstatus(conn) != CONNECTION_OK)
293  {
294  pg_log(PG_REPORT, "\nconnection to database failed: %s",
295  PQerrorMessage(conn));
296  if (conn)
297  PQfinish(conn);
298  if (cluster == &old_cluster)
299  pg_fatal("could not connect to source postmaster started with the command:\n"
300  "%s\n",
301  cmd);
302  else
303  pg_fatal("could not connect to target postmaster started with the command:\n"
304  "%s\n",
305  cmd);
306  }
307  PQfinish(conn);
308 
309  /*
310  * If pg_ctl failed, and the connection didn't fail, and
311  * report_and_exit_on_error is enabled, fail now. This could happen if
312  * the server was already running.
313  */
314  if (!pg_ctl_return)
315  {
316  if (cluster == &old_cluster)
317  pg_fatal("pg_ctl failed to start the source server, or connection failed\n");
318  else
319  pg_fatal("pg_ctl failed to start the target server, or connection failed\n");
320  }
321 
322  return true;
323 }
324 
325 
326 void
327 stop_postmaster(bool in_atexit)
328 {
330 
332  cluster = &old_cluster;
333  else if (os_info.running_cluster == &new_cluster)
334  cluster = &new_cluster;
335  else
336  return; /* no cluster running */
337 
338  exec_prog(SERVER_STOP_LOG_FILE, NULL, !in_atexit, !in_atexit,
339  "\"%s/pg_ctl\" -w -D \"%s\" -o \"%s\" %s stop",
340  cluster->bindir, cluster->pgconfig,
341  cluster->pgopts ? cluster->pgopts : "",
342  in_atexit ? "-m fast" : "-m smart");
343 
344  os_info.running_cluster = NULL;
345 }
346 
347 
348 /*
349  * check_pghost_envvar()
350  *
351  * Tests that PGHOST does not point to a non-local server
352  */
353 void
355 {
357  PQconninfoOption *start;
358 
359  /* Get valid libpq env vars from the PQconndefaults function */
360 
361  start = PQconndefaults();
362 
363  if (!start)
364  pg_fatal("out of memory\n");
365 
366  for (option = start; option->keyword != NULL; option++)
367  {
368  if (option->envvar && (strcmp(option->envvar, "PGHOST") == 0 ||
369  strcmp(option->envvar, "PGHOSTADDR") == 0))
370  {
371  const char *value = getenv(option->envvar);
372 
373  if (value && strlen(value) > 0 &&
374  /* check for 'local' host values */
375  (strcmp(value, "localhost") != 0 && strcmp(value, "127.0.0.1") != 0 &&
376  strcmp(value, "::1") != 0 && value[0] != '/'))
377  pg_fatal("libpq environment variable %s has a non-local server value: %s\n",
378  option->envvar, value);
379  }
380  }
381 
382  /* Free the memory that libpq allocated on our behalf */
383  PQconninfoFree(start);
384 }
char * cluster_conn_opts(ClusterInfo *cluster)
Definition: server.c:90
char * PQerrorMessage(const PGconn *conn)
Definition: fe-connect.c:6617
uint32 major_version
Definition: pg_upgrade.h:269
ControlData controldata
Definition: pg_upgrade.h:259
void termPQExpBuffer(PQExpBuffer str)
Definition: pqexpbuffer.c:131
void stop_postmaster(bool in_atexit)
Definition: server.c:327
void appendPQExpBufferStr(PQExpBuffer str, const char *data)
Definition: pqexpbuffer.c:369
#define GET_MAJOR_VERSION(v)
Definition: pg_upgrade.h:23
static struct @145 value
void appendConnStrVal(PQExpBuffer buf, const char *str)
Definition: string_utils.c:545
#define pg_fatal(...)
Definition: pg_rewind.h:43
void PQfinish(PGconn *conn)
Definition: fe-connect.c:4119
unsigned short port
Definition: pg_upgrade.h:268
#define printf(...)
Definition: port.h:198
ExecStatusType
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#define SERVER_STOP_LOG_FILE
Definition: pg_upgrade.h:54
PGconn * connectToServer(ClusterInfo *cluster, const char *db_name)
Definition: server.c:27
ExecStatusType PQresultStatus(const PGresult *res)
Definition: fe-exec.c:2692
char * pgopts
Definition: pg_upgrade.h:265
char major_version_str[64]
Definition: pg_upgrade.h:270
ClusterInfo new_cluster
Definition: pg_upgrade.c:59
char * pgconfig
Definition: pg_upgrade.h:262
bool start_postmaster(ClusterInfo *cluster, bool report_and_exit_on_error)
Definition: server.c:196
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Definition: streamutil.c:54
#define vsnprintf
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#define MAXPGPATH
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Definition: pqexpbuffer.c:267
static char * buf
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ClusterInfo old_cluster
Definition: pg_upgrade.c:59
unsigned int uint32
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void cluster(ClusterStmt *stmt, bool isTopLevel)
Definition: cluster.c:102
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Definition: server.c:120
void check_pghost_envvar(void)
Definition: server.c:354
char * bindir
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uint32 cat_ver
Definition: pg_upgrade.h:204
static void stop_postmaster_atexit(void)
Definition: server.c:189
PQExpBuffer createPQExpBuffer(void)
Definition: pqexpbuffer.c:74
void appendPQExpBufferChar(PQExpBuffer str, char ch)
Definition: pqexpbuffer.c:380
void PQclear(PGresult *res)
Definition: fe-exec.c:694
void appendShellString(PQExpBuffer buf, const char *str)
Definition: string_utils.c:429
#define SERVER_LOG_FILE
Definition: pg_upgrade.h:30
void void pg_log(eLogType type, const char *fmt,...) pg_attribute_printf(2
PQconninfoOption * PQconndefaults(void)
Definition: fe-connect.c:1372
#define ALWAYS_SECURE_SEARCH_PATH_SQL
Definition: connect.h:25
ClusterInfo * running_cluster
Definition: pg_upgrade.h:317
#define SERVER_START_LOG_FILE
Definition: pg_upgrade.h:53
char * pgdata
Definition: pg_upgrade.h:261
char * sockdir
Definition: pg_upgrade.h:267
OSInfo os_info
Definition: pg_upgrade.c:61
PGresult * PQexec(PGconn *conn, const char *query)
Definition: fe-exec.c:1939
#define BINARY_UPGRADE_SERVER_FLAG_CAT_VER
Definition: pg_upgrade.h:96
bool exec_prog(const char *log_file, const char *opt_log_file, bool report_error, bool exit_on_error, const char *fmt,...)
Definition: exec.c:80
void resetPQExpBuffer(PQExpBuffer str)
Definition: pqexpbuffer.c:148
static void static void status(const char *fmt,...) pg_attribute_printf(1
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ConnStatusType PQstatus(const PGconn *conn)
Definition: fe-connect.c:6564
uint32 get_major_server_version(ClusterInfo *cluster)
Definition: server.c:157
#define snprintf
Definition: port.h:192
char * user
Definition: pg_upgrade.h:311
static PGconn * get_db_conn(ClusterInfo *cluster, const char *db_name)
Definition: server.c:55
#define _(x)
Definition: elog.c:87
#define QUERY_ALLOC
Definition: pg_upgrade.h:19
void initPQExpBuffer(PQExpBuffer str)
Definition: pqexpbuffer.c:92
PGconn * PQconnectdb(const char *conninfo)
Definition: fe-connect.c:676