From f2491f9a1cfc261b21e475154a6bced37a28ea6e Mon Sep 17 00:00:00 2001
From: =?utf8?q?Ale=C5=A1=20K=C5=99enek?= <ljocha@ics.muni.cz>
Date: Thu, 21 Aug 2008 13:40:59 +0000
Subject: [PATCH] - compile-in SONAME of libmysqlclient.so, and insist on it at
 runtime - client version mismatch yields a warning only

---
 org.glite.lbjp-common.db/Makefile | 23 ++++++++++++-----------
 org.glite.lbjp-common.db/src/db.c | 18 ++++++------------
 2 files changed, 18 insertions(+), 23 deletions(-)

diff --git a/org.glite.lbjp-common.db/Makefile b/org.glite.lbjp-common.db/Makefile
index eb83e15..0fc856a 100644
--- a/org.glite.lbjp-common.db/Makefile
+++ b/org.glite.lbjp-common.db/Makefile
@@ -31,13 +31,10 @@ host_cpu:=${shell uname -m}
 ifeq (${host_cpu},x86_64) 
 	archlib:=lib64
 endif   
-ifeq ($(shell test -f ${mysql_prefix}/${archlib}/libmysqlclient.so && echo ok),ok)
-	MYSQL_LIBPATH := "$(wildcard ${mysql_prefix}/${archlib}/libmysqlclient.so*) $(notdir $(wildcard ${mysql_prefix}/${archlib}/libmysqlclient.so*))"
-endif
-ifeq ($(shell test -f ${mysql_prefix}/${archlib}/mysql/libmysqlclient.so && echo ok),ok)
-	MYSQL_LIBPATH := "$(wildcard ${mysql_prefix}/${archlib}/mysql/libmysqlclient.so*) $(notdir $(wildcard ${mysql_prefix}/${archlib}/mysql/libmysqlclient.so*))"
-endif
-MYSQL_CPPFLAGS:=-I${mysql_prefix}/include -I${mysql_prefix}/include/mysql -DMYSQL_LIBPATH=\"${MYSQL_LIBPATH}\"
+
+MYSQL_SONAME:=$(shell lib=/dev/null; for dir in '' mysql; do lib=${mysql_prefix}/${archlib}/$$dir/libmysqlclient.so; [ -f $$lib ] && break; done; readelf -d $$lib | grep SONAME | sed 's/.*\(libmysqlclient.so.[0-9]\{1,\}\).*/\1/' || echo notfound )
+
+MYSQL_CPPFLAGS:=-I${mysql_prefix}/include -I${mysql_prefix}/include/mysql -DMYSQL_SONAME=\"${MYSQL_SONAME}\"
 MYSQL_LIBS=-lz
 
 CFLAGS:= \
@@ -71,11 +68,15 @@ LTESTOBJS:=${TESTOBJS:.o=.lo}
 
 default all: compile doc
 
-libglite_lbu_db.la: ${LOBJS}
-	if [ -z "${MYSQL_LIBPATH}" ]; then \
-		echo "Warning: MySQL shared library not found!"; \
-		sleep 15; \
+check_soname:
+	if [ "${MYSQL_SONAME}" = notfound ]; then \
+		echo "MySQL shared library not found!"; \
+		false; \
 	fi
+
+db.lo: check_soname
+
+libglite_lbu_db.la: ${LOBJS}
 	${LINK} -o $@ $< ${EXT_LIBS}
 
 libglite_lbu_dbtest.la: ${LTESTOBJS}
diff --git a/org.glite.lbjp-common.db/src/db.c b/org.glite.lbjp-common.db/src/db.c
index c944245..f60b3d9 100644
--- a/org.glite.lbjp-common.db/src/db.c
+++ b/org.glite.lbjp-common.db/src/db.c
@@ -14,6 +14,7 @@
 #include <stdarg.h>
 #include <dlfcn.h>
 #include <pthread.h>
+#include <syslog.h>
 
 #include <mysql.h>
 #include <mysqld_error.h>
@@ -185,7 +186,6 @@ int glite_lbu_DBError(glite_lbu_DBContext ctx, char **text, char **desc) {
 int glite_lbu_InitDBContext(glite_lbu_DBContext *ctx) {
 	int err = 0;
 	unsigned int ver_u;
-	char *p, *libnames, *libname;
 
 	*ctx = calloc(1, sizeof **ctx);
 	if (!*ctx) return ENOMEM;
@@ -193,14 +193,8 @@ int glite_lbu_InitDBContext(glite_lbu_DBContext *ctx) {
 	/* dynamic load the mysql library */
 	pthread_mutex_lock(&db_handle.lock);
 	if (!db_handle.lib) {
-		libnames = strdup(MYSQL_LIBPATH " libmysqlclient.so");
-		libname = strtok_r(libnames, " ", &p);
-		while (libname) {
-			libname = strtok_r(NULL, " ", &p);
-			if ((db_handle.lib = dlopen(libname, RTLD_LAZY | RTLD_LOCAL)) != NULL) break;
-		}
-		free(libnames);
-		if (!db_handle.lib) return ERR(*ctx, ENOENT, "can't load libmysqlclient library (%s), tried: ", dlerror(), MYSQL_LIBPATH " libmysqlclient.so");
+		db_handle.lib = dlopen(MYSQL_SONAME, RTLD_LAZY | RTLD_LOCAL);
+		if (!db_handle.lib) return ERR(*ctx, ENOENT, "dlopen(): " MYSQL_SONAME ": %s", dlerror());
 		do {
 			LOAD(mysql_init, "mysql_init");
 			LOAD(mysql_get_client_version, "mysql_get_client_version");
@@ -236,8 +230,8 @@ int glite_lbu_InitDBContext(glite_lbu_DBContext *ctx) {
 			// check the runtime version
 			ver_u = db_handle.mysql_get_client_version();
 			if (ver_u != MYSQL_VERSION_ID) {
-				err = ERR(*ctx, EINVAL, "version mismatch (compiled '%lu', runtime '%lu')", MYSQL_VERSION_ID, ver_u);
-				break;
+				fprintf(stderr,"Warning: MySQL library version mismatch (compiled '%lu', runtime '%lu')", MYSQL_VERSION_ID, ver_u);
+				syslog(LOG_WARNING,"MySQL library version mismatch (compiled '%lu', runtime '%lu')", MYSQL_VERSION_ID, ver_u);
 			}
 
 			pthread_mutex_unlock(&db_handle.lock);
@@ -904,7 +898,7 @@ static int lbu_err(glite_lbu_DBContext ctx, int code, const char *func, int line
 			va_end(ap);
 		} else
 			ctx->err.desc = NULL;
-		dprintf(ctx, "[db %d] %s:%d %s\n", getpid(), func, line, desc);
+		dprintf(ctx, "[db %d] %s:%d %s\n", getpid(), func, line, desc ? ctx->err.desc : "");
 		return code;
 	} else
 		return ctx->err.code;
-- 
1.8.2.3