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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-05 17:28:19 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-05 17:28:19 +0000
commit18657a960e125336f704ea058e25c27bd3900dcb (patch)
tree17b438b680ed45a996d7b59951e6aa34023783f2 /ext/misc/memtrace.c
parentInitial commit. (diff)
downloadsqlite3-upstream.tar.xz
sqlite3-upstream.zip
Adding upstream version 3.40.1.upstream/3.40.1upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'ext/misc/memtrace.c')
-rw-r--r--ext/misc/memtrace.c108
1 files changed, 108 insertions, 0 deletions
diff --git a/ext/misc/memtrace.c b/ext/misc/memtrace.c
new file mode 100644
index 0000000..19ff4c4
--- /dev/null
+++ b/ext/misc/memtrace.c
@@ -0,0 +1,108 @@
+/*
+** 2019-01-21
+**
+** The author disclaims copyright to this source code. In place of
+** a legal notice, here is a blessing:
+**
+** May you do good and not evil.
+** May you find forgiveness for yourself and forgive others.
+** May you share freely, never taking more than you give.
+**
+*************************************************************************
+**
+** This file implements an extension that uses the SQLITE_CONFIG_MALLOC
+** mechanism to add a tracing layer on top of SQLite. If this extension
+** is registered prior to sqlite3_initialize(), it will cause all memory
+** allocation activities to be logged on standard output, or to some other
+** FILE specified by the initializer.
+**
+** This file needs to be compiled into the application that uses it.
+**
+** This extension is used to implement the --memtrace option of the
+** command-line shell.
+*/
+#include <assert.h>
+#include <string.h>
+#include <stdio.h>
+
+/* The original memory allocation routines */
+static sqlite3_mem_methods memtraceBase;
+static FILE *memtraceOut;
+
+/* Methods that trace memory allocations */
+static void *memtraceMalloc(int n){
+ if( memtraceOut ){
+ fprintf(memtraceOut, "MEMTRACE: allocate %d bytes\n",
+ memtraceBase.xRoundup(n));
+ }
+ return memtraceBase.xMalloc(n);
+}
+static void memtraceFree(void *p){
+ if( p==0 ) return;
+ if( memtraceOut ){
+ fprintf(memtraceOut, "MEMTRACE: free %d bytes\n", memtraceBase.xSize(p));
+ }
+ memtraceBase.xFree(p);
+}
+static void *memtraceRealloc(void *p, int n){
+ if( p==0 ) return memtraceMalloc(n);
+ if( n==0 ){
+ memtraceFree(p);
+ return 0;
+ }
+ if( memtraceOut ){
+ fprintf(memtraceOut, "MEMTRACE: resize %d -> %d bytes\n",
+ memtraceBase.xSize(p), memtraceBase.xRoundup(n));
+ }
+ return memtraceBase.xRealloc(p, n);
+}
+static int memtraceSize(void *p){
+ return memtraceBase.xSize(p);
+}
+static int memtraceRoundup(int n){
+ return memtraceBase.xRoundup(n);
+}
+static int memtraceInit(void *p){
+ return memtraceBase.xInit(p);
+}
+static void memtraceShutdown(void *p){
+ memtraceBase.xShutdown(p);
+}
+
+/* The substitute memory allocator */
+static sqlite3_mem_methods ersaztMethods = {
+ memtraceMalloc,
+ memtraceFree,
+ memtraceRealloc,
+ memtraceSize,
+ memtraceRoundup,
+ memtraceInit,
+ memtraceShutdown,
+ 0
+};
+
+/* Begin tracing memory allocations to out. */
+int sqlite3MemTraceActivate(FILE *out){
+ int rc = SQLITE_OK;
+ if( memtraceBase.xMalloc==0 ){
+ rc = sqlite3_config(SQLITE_CONFIG_GETMALLOC, &memtraceBase);
+ if( rc==SQLITE_OK ){
+ rc = sqlite3_config(SQLITE_CONFIG_MALLOC, &ersaztMethods);
+ }
+ }
+ memtraceOut = out;
+ return rc;
+}
+
+/* Deactivate memory tracing */
+int sqlite3MemTraceDeactivate(void){
+ int rc = SQLITE_OK;
+ if( memtraceBase.xMalloc!=0 ){
+ rc = sqlite3_config(SQLITE_CONFIG_MALLOC, &memtraceBase);
+ if( rc==SQLITE_OK ){
+ memset(&memtraceBase, 0, sizeof(memtraceBase));
+ }
+ }
+ memtraceOut = 0;
+ return rc;
+}