From ce4ab06fab7fa7989caf914329067132b4dbe897 Mon Sep 17 00:00:00 2001
From: Marius Tolzmann <tolzmann@molgen.mpg.de>
Date: Fri, 22 May 2015 17:12:10 +0200
Subject: [PATCH] mx_mysql: Redesign mx_mysql_statement_prepare()

---
 mx_mysql.c | 52 ++++++++++++++++++++++++++++++----------------------
 mx_mysql.h |  2 +-
 mxqsub.c   | 30 +++++++++---------------------
 3 files changed, 40 insertions(+), 44 deletions(-)

diff --git a/mx_mysql.c b/mx_mysql.c
index ece305c..d61fb8e 100644
--- a/mx_mysql.c
+++ b/mx_mysql.c
@@ -1110,38 +1110,46 @@ int mx_mysql_bind_init(struct mx_mysql_bind *bind, unsigned long count)
     return 0;
 }
 
-int mx_mysql_statement_prepare(struct mx_mysql_stmt *stmt, char *statement)
+struct mx_mysql_stmt *mx_mysql_statement_prepare(struct mx_mysql *mysql, char *statement)
 {
     int res;
+    struct mx_mysql_stmt *stmt = NULL;
 
-    mx_assert_return_minus_errno(stmt, EINVAL);
+    mx_assert_return_NULL(mysql, EINVAL);
+    mx_assert_return_NULL(statement, EINVAL);
+    mx_assert_return_NULL(*statement, EINVAL);
 
-    res = mx__mysql_stmt_prepare(stmt, statement);
-    mx_mysql_assert_usage_ok(res);
+    res = mx_mysql_statement_init(mysql, &stmt);
     if (res < 0)
-        return res;
+        return NULL;
 
-    res = mx_mysql_stmt_param_count_set(stmt);
-    mx_mysql_assert_usage_ok(res);
-    if (res < 0)
-        return res;
+    while (1) {
+        res = mx__mysql_stmt_prepare(stmt, statement);
+        if (res < 0)
+            break;
 
-    res = mx_mysql_stmt_field_count_set(stmt);
-    mx_mysql_assert_usage_ok(res);
-    if (res < 0)
-        return res;
+        res = mx_mysql_stmt_param_count_set(stmt);
+        if (res < 0)
+            break;
 
-    res = mx_mysql_bind_init(&stmt->param, stmt->param_count);
-    mx_mysql_assert_usage_ok(res);
-    if (res < 0)
-        return res;
+        res = mx_mysql_stmt_field_count_set(stmt);
+        if (res < 0)
+            break;
 
-    res = mx_mysql_bind_init(&stmt->result, stmt->field_count);
-    mx_mysql_assert_usage_ok(res);
-    if (res < 0)
-        return res;
+        res = mx_mysql_bind_init(&stmt->param, stmt->param_count);
+        if (res < 0)
+            break;
 
-    return 0;
+        res = mx_mysql_bind_init(&stmt->result, stmt->field_count);
+        if (res < 0)
+            break;
+
+        return stmt;
+    };
+
+    mx_mysql_statement_close(&stmt);
+
+    return NULL;
 }
 
 int mx_mysql_statement_close(struct mx_mysql_stmt **stmt)
diff --git a/mx_mysql.h b/mx_mysql.h
index 02e8348..04ececb 100644
--- a/mx_mysql.h
+++ b/mx_mysql.h
@@ -114,7 +114,7 @@ int mx_mysql_end(void);
 int mx_mysql_finish(struct mx_mysql **mysql);
 
 int mx_mysql_statement_init(struct mx_mysql *mysql, struct mx_mysql_stmt **stmt);
-int mx_mysql_statement_prepare(struct mx_mysql_stmt *stmt, char *statement);
+struct mx_mysql_stmt *mx_mysql_statement_prepare(struct mx_mysql *mysql, char *statement);
 int mx_mysql_statement_execute(struct mx_mysql_stmt *stmt, unsigned long long *count);
 
 int mx_mysql_statement_insert_id(struct mx_mysql_stmt *stmt, unsigned long long int *id);
diff --git a/mxqsub.c b/mxqsub.c
index 0361a6a..3adfe06 100644
--- a/mxqsub.c
+++ b/mxqsub.c
@@ -164,11 +164,7 @@ static int load_group_id(struct mx_mysql *mysql, struct mxq_group *g)
     assert(g->job_command); assert(*g->job_command);
     assert(g->job_threads); assert(g->job_memory); assert(g->job_time);
 
-    res = mx_mysql_statement_init(mysql, &stmt);
-    if (res < 0)
-        return res;
-
-    res = mx_mysql_statement_prepare(stmt,
+    stmt = mx_mysql_statement_prepare(mysql,
             "SELECT"
                 " group_id"
             " FROM mxq_group "
@@ -185,9 +181,9 @@ static int load_group_id(struct mx_mysql *mysql, struct mxq_group *g)
                 " AND group_status = 0"
             " ORDER BY group_id "
             " LIMIT 1");
-    if (res < 0) {
+    if (!stmt) {
         mx_log_err("mx_mysql_statement_prepare(): %m");
-        return res;
+        return -errno;
     }
 
     res  = mx_mysql_statement_param_bind(stmt, 0, string, &(g->group_name));
@@ -238,11 +234,7 @@ static int add_group(struct mx_mysql *mysql, struct mxq_group *g)
     assert(g->job_command); assert(*g->job_command);
     assert(g->job_threads); assert(g->job_memory); assert(g->job_time);
 
-    res = mx_mysql_statement_init(mysql, &stmt);
-    if (res < 0)
-        return res;
-
-    res = mx_mysql_statement_prepare(stmt,
+    stmt = mx_mysql_statement_prepare(mysql,
             "INSERT INTO mxq_group SET"
                 " group_name = ?,"
 
@@ -257,9 +249,9 @@ static int add_group(struct mx_mysql *mysql, struct mxq_group *g)
                 " job_memory = ?,"
                 " job_time = ?,"
                 " group_priority = ?");
-    if (res < 0) {
+    if (!stmt) {
         mx_log_err("mx_mysql_statement_prepare(): %m");
-        return res;
+        return -errno;
     }
 
     res  = mx_mysql_statement_param_bind(stmt, 0, string, &(g->group_name));
@@ -308,11 +300,7 @@ static int add_job(struct mx_mysql *mysql, struct mxq_job *j)
     assert(j->job_umask);
     assert(j->host_submit); assert(*j->host_submit);
 
-    res = mx_mysql_statement_init(mysql, &stmt);
-    if (res < 0)
-        return res;
-
-    res = mx_mysql_statement_prepare(stmt,
+    stmt = mx_mysql_statement_prepare(mysql,
             "INSERT INTO mxq_job SET"
                 " job_priority = ?,"
 
@@ -331,10 +319,10 @@ static int add_job(struct mx_mysql *mysql, struct mxq_job *j)
 
                 " job_flags = ?"
                 );
-    if (res < 0) {
+    if (!stmt) {
         mx_log_err("mx_mysql_statement_prepare(): %m");
         mx_mysql_statement_close(&stmt);
-        return res;
+        return -errno;
     }
 
     res  = mx_mysql_statement_param_bind(stmt, 0, uint16, &(j->job_priority));