Add SQLite3 debug logging if PROJ_LOG_SQLITE3 env var is defined

1 files changed, 17 insertions, 0 deletions

diff --git a/src/sqlite3_utils.cpp b/src/sqlite3_utils.cpp
index 7006674f..84bbb2ce 100644
--- a/src/sqlite3_utils.cpp
+++ b/src/sqlite3_utils.cpp
@@ -133,8 +133,25 @@ static int VFSCustomAccess(sqlite3_vfs *vfs, const char *zName, int flags,
 
 // ---------------------------------------------------------------------------
 
+// SQLite3 logging infrastructure
+static void projSqlite3LogCallback(void *, int iErrCode, const char *zMsg) {
+    fprintf(stderr, "SQLite3 message: (code %d) %s\n", iErrCode, zMsg);
+}
+
 std::unique_ptr<SQLite3VFS> SQLite3VFS::create(bool fakeSync, bool fakeLock,
                                                bool skipStatJournalAndWAL) {
+
+    // Install SQLite3 logger if PROJ_LOG_SQLITE3 env var is defined
+    struct InstallSqliteLogger {
+        InstallSqliteLogger() {
+            if (getenv("PROJ_LOG_SQLITE3") != nullptr) {
+                sqlite3_config(SQLITE_CONFIG_LOG, projSqlite3LogCallback,
+                               nullptr);
+            }
+        }
+    };
+    static InstallSqliteLogger installSqliteLogger;
+
     // Call to sqlite3_initialize() is normally not needed, except for
     // people building SQLite3 with -DSQLITE_OMIT_AUTOINIT
     sqlite3_initialize();