diff options
Diffstat (limited to 'src/bin/pg_dump/connectdb.c')
-rw-r--r-- | src/bin/pg_dump/connectdb.c | 294 |
1 files changed, 294 insertions, 0 deletions
diff --git a/src/bin/pg_dump/connectdb.c b/src/bin/pg_dump/connectdb.c new file mode 100644 index 00000000000..9e593b70e81 --- /dev/null +++ b/src/bin/pg_dump/connectdb.c @@ -0,0 +1,294 @@ +/*------------------------------------------------------------------------- + * + * connectdb.c + * This is a common file connection to the database. + * + * Portions Copyright (c) 1996-2025, PostgreSQL Global Development Group + * Portions Copyright (c) 1994, Regents of the University of California + * + * IDENTIFICATION + * src/bin/pg_dump/connectdb.c + * + *------------------------------------------------------------------------- + */ + +#include "postgres_fe.h" + +#include "common/connect.h" +#include "common/logging.h" +#include "common/string.h" +#include "connectdb.h" +#include "dumputils.h" +#include "fe_utils/string_utils.h" + +static char *constructConnStr(const char **keywords, const char **values); + +/* + * ConnectDatabase + * + * Make a database connection with the given parameters. An + * interactive password prompt is automatically issued if required. + * + * If fail_on_error is false, we return NULL without printing any message + * on failure, but preserve any prompted password for the next try. + * + * On success, the 'connstr' is set to a connection string containing + * the options used and 'server_version' is set to version so that caller + * can use them. + */ +PGconn * +ConnectDatabase(const char *dbname, const char *connection_string, + const char *pghost, const char *pgport, const char *pguser, + trivalue prompt_password, bool fail_on_error, const char *progname, + const char **connstr, int *server_version, char *password, + char *override_dbname) +{ + PGconn *conn; + bool new_pass; + const char *remoteversion_str; + int my_version; + const char **keywords = NULL; + const char **values = NULL; + PQconninfoOption *conn_opts = NULL; + int server_version_temp; + + if (prompt_password == TRI_YES && !password) + password = simple_prompt("Password: ", false); + + /* + * Start the connection. Loop until we have a password if requested by + * backend. + */ + do + { + int argcount = 8; + PQconninfoOption *conn_opt; + char *err_msg = NULL; + int i = 0; + + free(keywords); + free(values); + PQconninfoFree(conn_opts); + + /* + * Merge the connection info inputs given in form of connection string + * and other options. Explicitly discard any dbname value in the + * connection string; otherwise, PQconnectdbParams() would interpret + * that value as being itself a connection string. + */ + if (connection_string) + { + conn_opts = PQconninfoParse(connection_string, &err_msg); + if (conn_opts == NULL) + pg_fatal("%s", err_msg); + + for (conn_opt = conn_opts; conn_opt->keyword != NULL; conn_opt++) + { + if (conn_opt->val != NULL && conn_opt->val[0] != '\0' && + strcmp(conn_opt->keyword, "dbname") != 0) + argcount++; + } + + keywords = pg_malloc0((argcount + 1) * sizeof(*keywords)); + values = pg_malloc0((argcount + 1) * sizeof(*values)); + + for (conn_opt = conn_opts; conn_opt->keyword != NULL; conn_opt++) + { + if (conn_opt->val != NULL && conn_opt->val[0] != '\0' && + strcmp(conn_opt->keyword, "dbname") != 0) + { + keywords[i] = conn_opt->keyword; + values[i] = conn_opt->val; + i++; + } + } + } + else + { + keywords = pg_malloc0((argcount + 1) * sizeof(*keywords)); + values = pg_malloc0((argcount + 1) * sizeof(*values)); + } + + if (pghost) + { + keywords[i] = "host"; + values[i] = pghost; + i++; + } + if (pgport) + { + keywords[i] = "port"; + values[i] = pgport; + i++; + } + if (pguser) + { + keywords[i] = "user"; + values[i] = pguser; + i++; + } + if (password) + { + keywords[i] = "password"; + values[i] = password; + i++; + } + if (dbname) + { + keywords[i] = "dbname"; + values[i] = dbname; + i++; + } + if (override_dbname) + { + keywords[i] = "dbname"; + values[i++] = override_dbname; + } + + keywords[i] = "fallback_application_name"; + values[i] = progname; + i++; + + new_pass = false; + conn = PQconnectdbParams(keywords, values, true); + + if (!conn) + pg_fatal("could not connect to database \"%s\"", dbname); + + if (PQstatus(conn) == CONNECTION_BAD && + PQconnectionNeedsPassword(conn) && + !password && + prompt_password != TRI_NO) + { + PQfinish(conn); + password = simple_prompt("Password: ", false); + new_pass = true; + } + } while (new_pass); + + /* check to see that the backend connection was successfully made */ + if (PQstatus(conn) == CONNECTION_BAD) + { + if (fail_on_error) + pg_fatal("%s", PQerrorMessage(conn)); + else + { + PQfinish(conn); + + free(keywords); + free(values); + PQconninfoFree(conn_opts); + + return NULL; + } + } + + /* + * Ok, connected successfully. If requested, remember the options used, in + * the form of a connection string. + */ + if (connstr) + *connstr = constructConnStr(keywords, values); + + free(keywords); + free(values); + PQconninfoFree(conn_opts); + + /* Check version */ + remoteversion_str = PQparameterStatus(conn, "server_version"); + if (!remoteversion_str) + pg_fatal("could not get server version"); + + server_version_temp = PQserverVersion(conn); + if (server_version_temp == 0) + pg_fatal("could not parse server version \"%s\"", + remoteversion_str); + + /* If requested, then copy server version to out variable. */ + if (server_version) + *server_version = server_version_temp; + + my_version = PG_VERSION_NUM; + + /* + * We allow the server to be back to 9.2, and up to any minor release of + * our own major version. (See also version check in pg_dump.c.) + */ + if (my_version != server_version_temp + && (server_version_temp < 90200 || + (server_version_temp / 100) > (my_version / 100))) + { + pg_log_error("aborting because of server version mismatch"); + pg_log_error_detail("server version: %s; %s version: %s", + remoteversion_str, progname, PG_VERSION); + exit_nicely(1); + } + + PQclear(executeQuery(conn, ALWAYS_SECURE_SEARCH_PATH_SQL)); + + return conn; +} + +/* + * constructConnStr + * + * Construct a connection string from the given keyword/value pairs. It is + * used to pass the connection options to the pg_dump subprocess. + * + * The following parameters are excluded: + * dbname - varies in each pg_dump invocation + * password - it's not secure to pass a password on the command line + * fallback_application_name - we'll let pg_dump set it + */ +static char * +constructConnStr(const char **keywords, const char **values) +{ + PQExpBuffer buf = createPQExpBuffer(); + char *connstr; + int i; + bool firstkeyword = true; + + /* Construct a new connection string in key='value' format. */ + for (i = 0; keywords[i] != NULL; i++) + { + if (strcmp(keywords[i], "dbname") == 0 || + strcmp(keywords[i], "password") == 0 || + strcmp(keywords[i], "fallback_application_name") == 0) + continue; + + if (!firstkeyword) + appendPQExpBufferChar(buf, ' '); + firstkeyword = false; + appendPQExpBuffer(buf, "%s=", keywords[i]); + appendConnStrVal(buf, values[i]); + } + + connstr = pg_strdup(buf->data); + destroyPQExpBuffer(buf); + return connstr; +} + +/* + * executeQuery + * + * Run a query, return the results, exit program on failure. + */ +PGresult * +executeQuery(PGconn *conn, const char *query) +{ + PGresult *res; + + pg_log_info("executing %s", query); + + res = PQexec(conn, query); + if (!res || + PQresultStatus(res) != PGRES_TUPLES_OK) + { + pg_log_error("query failed: %s", PQerrorMessage(conn)); + pg_log_error_detail("Query was: %s", query); + PQfinish(conn); + exit_nicely(1); + } + + return res; +} |