res_config_pgsql: Limit realtime_pgsql() to return one (no more) record.

Added a SELECT 'LIMIT' clause to realtime_pgsql() and refactored the function.

ASTERISK-29293 #close

Change-Id: If5a6d4b1072ea2e6e89059b21139d554a74b34f5

diff --git a/res/res_config_pgsql.c b/res/res_config_pgsql.c
index 63eabf83076c72fd2de4c9f0a286a37c2307f1a0..6f49f8e791af696842c3e33560e17210b4f9ed23 100644 (file)
--- a/res/res_config_pgsql.c
+++ b/res/res_config_pgsql.c
@@ -390,7 +390,7 @@ static struct columns *find_column(struct tables *t, const char *colname)
 static struct ast_variable *realtime_pgsql(const char *database, const char *tablename, const struct ast_variable *fields)
 {
        RAII_VAR(PGresult *, result, NULL, PQclear);
-       int num_rows = 0, pgresult;
+       int pgresult;
        struct ast_str *sql = ast_str_thread_get(&sql_buf, 100);
        struct ast_str *escapebuf = ast_str_thread_get(&escapebuf_buf, 100);
        char *stringp;
@@ -472,6 +472,7 @@ static struct ast_variable *realtime_pgsql(const char *database, const char *tab
 
                ast_str_append(&sql, 0, " AND %s%s '%s'%s", field->name, op, ast_str_buffer(escapebuf), escape);
        }
+       ast_str_append(&sql, 0, " LIMIT 1");
 
        /* We now have our complete statement; Lets connect to the server and execute it. */
         if (pgsql_exec(database, tablename, ast_str_buffer(sql), &result) != 0) {
@@ -481,13 +482,12 @@ static struct ast_variable *realtime_pgsql(const char *database, const char *tab
 
        ast_debug(1, "PostgreSQL RealTime: Result=%p Query: %s\n", result, ast_str_buffer(sql));
 
-       if ((num_rows = PQntuples(result)) > 0) {
+       if (PQntuples(result) > 0) {
                int i = 0;
-               int rowIndex = 0;
                int numFields = PQnfields(result);
                char **fieldnames = NULL;
 
-               ast_debug(1, "PostgreSQL RealTime: Found %d rows.\n", num_rows);
+               ast_debug(1, "PostgreSQL RealTime: Found a row.\n");
 
                if (!(fieldnames = ast_calloc(1, numFields * sizeof(char *)))) {
                        ast_mutex_unlock(&pgsql_lock);
@@ -495,20 +495,18 @@ static struct ast_variable *realtime_pgsql(const char *database, const char *tab
                }
                for (i = 0; i < numFields; i++)
                        fieldnames[i] = PQfname(result, i);
-               for (rowIndex = 0; rowIndex < num_rows; rowIndex++) {
-                       for (i = 0; i < numFields; i++) {
-                               stringp = PQgetvalue(result, rowIndex, i);
-                               while (stringp) {
-                                       chunk = strsep(&stringp, ";");
-                                       if (chunk && !ast_strlen_zero(ast_realtime_decode_chunk(ast_strip(chunk)))) {
-                                               if (prev) {
-                                                       prev->next = ast_variable_new(fieldnames[i], chunk, "");
-                                                       if (prev->next) {
-                                                               prev = prev->next;
-                                                       }
-                                               } else {
-                                                       prev = var = ast_variable_new(fieldnames[i], chunk, "");
+               for (i = 0; i < numFields; i++) {
+                       stringp = PQgetvalue(result, 0, i);
+                       while (stringp) {
+                               chunk = strsep(&stringp, ";");
+                               if (chunk && !ast_strlen_zero(ast_realtime_decode_chunk(ast_strip(chunk)))) {
+                                       if (prev) {
+                                               prev->next = ast_variable_new(fieldnames[i], chunk, "");
+                                               if (prev->next) {
+                                                       prev = prev->next;
                                                }
+                                       } else {
+                                               prev = var = ast_variable_new(fieldnames[i], chunk, "");
                                        }
                                }
                        }