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-rw-r--r--chattymalloc.c469
1 files changed, 30 insertions, 439 deletions
diff --git a/chattymalloc.c b/chattymalloc.c
index 301e0f2..f3db0d2 100644
--- a/chattymalloc.c
+++ b/chattymalloc.c
@@ -1,278 +1,60 @@
#define _GNU_SOURCE
#include <dlfcn.h>
-#include <stdbool.h>
#include <stddef.h>
-#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
-#include <time.h>
-#include <signal.h>
-#include <sys/syscall.h>
-#include <unistd.h>
-static void * (*myfn_malloc)(size_t size);
-static void * (*myfn_free)(void* ptr);
-static void * (*myfn_calloc)(size_t nmemb, size_t size);
-static void * (*myfn_realloc)(void *ptr, size_t size);
-static void * (*myfn_memalign)(size_t blocksize, size_t bytes);
-
-static int initializing = 0;
+char tmpbuff[1024];
+unsigned long tmppos = 0;
+unsigned long tmpallocs = 0;
-// Memory we give out during initialisation
-static char tmpbuff[4096];
-static unsigned long tmppos = 0;
-static unsigned long tmpallocs = 0;
-
-/* Options that can be set in the CHATTYMALLOC_OPTS environment var.
- *
- * store: store call data in memory or dump it with each allocator call */
-static bool store = true;
-/* sigusr1: dump in memory log in SIGUSR1 handler */
-static bool sigusr1 = false;
-/* timestamp: get timestamp of each allocator call */
-static bool timestamp = false;
-/* timestamp: get timestamp of each allocator call */
-static char* path = "chattymalloc.data";
-
-void parse_options()
-{
- char* options = getenv("CHATTYMALLOC_OPTS");
- if (!options)
- return;
-
- char* opt = options;
- char* val;
- char c;
-
- for (int i = 0;; i++)
- {
- c = options[i];
- if (c == ':' || c == '\0')
- {
- if (strncmp(opt, "store", 5) == 0)
- {
- if (strncmp(val, "false", 5) == 0)
- store = false;
- }
- else if (strncmp(opt, "sigusr1", 7) == 0)
- {
- if (strncmp(val, "true", 4) == 0)
- sigusr1 = true;
- }
- else if (strncmp(opt, "timestamp", 9) == 0)
- {
- if (strncmp(val, "true", 4) == 0)
- timestamp = true;
- }
- else
- fprintf(stderr, "Unknown option \n");
+FILE* out = NULL;
- if (c == '\0')
- return;
+/*=========================================================
+ * * interception points
+ * */
- opt = options + i + 1;
- }
- else if (c == '=')
- {
- val = options + i + 1;
- }
- }
-}
-
-typedef enum { MALLOC, FREE, CALLOC, REALLOC, MEMALIGN } Func;
-
-// Entry in our in memory log
-typedef struct Log_entry
-{
- time_t time;
- Func function;
- uintptr_t args[3];
-} Log_entry;
-
-// Chunk of thread local log entries
-typedef struct Log_chunk
-{
- struct Log_chunk* next;
- pid_t tid;
- size_t n;
- Log_entry entries[10000];
-} Log_chunk;
-
-// List of chunks
-static struct Log_chunk* log_start = NULL;
-static struct Log_chunk* log_end = NULL;
-
-static __thread pid_t tid;
-static __thread Log_chunk* cur_log;
-
-// Flag to prevent recursion
-static __thread int prevent_recursion = 0;
-
-static void (*old_signalhandler)(int);
-
-FILE* out;
-
-#ifdef SYS_gettid
-static pid_t gettid()
-{
- if (!tid)
- tid = syscall(SYS_gettid);
- return tid;
-}
-#else
-#error "SYS_gettid unavailable on this system"
-#endif
-
-static void open_output()
-{
- out = fopen(path, "w");
- if (!out)
- {
- perror("failed to open output");
- exit(1);
- }
-}
+static void * (*myfn_malloc)(size_t size);
+static void * (*myfn_free)(void* ptr);
-static void new_log_chunk (void)
+static void init()
{
- cur_log = myfn_malloc(sizeof(Log_chunk));
- if (!cur_log)
+ out = fopen("chattymalloc.data", "w");
+ if (out == NULL)
{
- perror("can't malloc chunk");
+ fprintf(stderr, "failed to open output file\n");
exit(1);
}
- cur_log->tid = gettid();
- cur_log->n = 0;
- cur_log->next = NULL;
-
-chain: ;
- Log_chunk* old_end = log_end;
- if (!__sync_bool_compare_and_swap(&log_end, old_end, cur_log))
- goto chain;
-
- if (old_end)
- old_end->next = cur_log;
-}
-
-static void write_log (void)
-{
- Log_chunk* chunk = log_start;
-
- prevent_recursion = 1;
-
- open_output();
-
- while (chunk)
- {
- for (size_t i = 0; i < chunk->n; i++)
- {
- Log_entry entry = chunk->entries[i];
- fprintf(out, "%lu %d ", entry.time, chunk->tid);
- switch (entry.function)
- {
- case MALLOC:
- fprintf(out, "ma %lu %p\n", entry.args[0], entry.args[1]);
- break;
- case FREE:
- fprintf(out, "f %p\n", entry.args[0]);
- break;
- case CALLOC:
- fprintf(out, "c %lu %lu %p\n", entry.args[0], entry.args[1], entry.args[2]);
- break;
- case REALLOC:
- fprintf(out, "r %p %lu %p\n", entry.args[0], entry.args[1], entry.args[2]);
- break;
- case MEMALIGN:
- fprintf(out, "mm %lu %lu %p\n", entry.args[0], entry.args[1], entry.args[2]);
- break;
- }
- }
- chunk = chunk->next;
- }
-
- fclose(out);
-}
-
-static void sigusr1_handler
-(int __attribute__((__unused__)) sig)
-{
- write_log();
- pid_t ppid = getppid();
- kill(ppid, SIGUSR1);
-
- // we are done writing the log
- prevent_recursion = 0;
-}
-
-static void init (void)
-{
- initializing = 1;
-
myfn_malloc = dlsym(RTLD_NEXT, "malloc");
myfn_free = dlsym(RTLD_NEXT, "free");
- myfn_calloc = dlsym(RTLD_NEXT, "calloc");
- myfn_realloc = dlsym(RTLD_NEXT, "realloc");
- myfn_memalign = dlsym(RTLD_NEXT, "memalign");
- if (!myfn_malloc || !myfn_free || !myfn_calloc || !myfn_realloc || !myfn_memalign)
+ if (!myfn_malloc || !myfn_free)
{
fprintf(stderr, "Error in `dlsym`: %s\n", dlerror());
exit(1);
}
-
- initializing = 0;
- // now we can use the real allocator
- prevent_recursion = 1;
-
- // parse chattymalloc options
- parse_options();
-
- if (store)
- {
- new_log_chunk();
- log_start = cur_log;
- atexit(write_log);
- }
- else
- open_output();
-
- if (sigusr1)
- {
- // register USR1 signal handler to dump log
- struct sigaction old;
- struct sigaction sa;
-
- sigaction(SIGUSR1, NULL, &old);
- old_signalhandler = old.sa_handler;
-
- memset(&sa, 0, sizeof(sa));
- sa.sa_handler = sigusr1_handler;
- sa.sa_mask = old.sa_mask;
-
- if (sigaction(SIGUSR1, &sa, NULL) == -1)
- {
- perror("Can't register our SIGUSR1 handler");
- exit(1);
- }
- }
-
- prevent_recursion = 0;
}
-void *malloc (size_t size)
+void *malloc(size_t size)
{
+ static int initializing = 0;
+ static int in_fprintf = 0;
if (myfn_malloc == NULL)
{
if (!initializing)
+ {
+ initializing = 1;
init();
+ initializing = 0;
+
+ }
else
{
if (tmppos + size < sizeof(tmpbuff))
{
- /* fprintf(stderr, "jcheck: %lu requested during init\n", size); */
void *retptr = tmpbuff + tmppos;
tmppos += size;
++tmpallocs;
@@ -281,217 +63,26 @@ void *malloc (size_t size)
else
{
fprintf(stderr, "jcheck: too much memory requested during initialisation - increase tmpbuff size\n");
- *((int*) NULL) = 1;
exit(1);
}
}
}
- void *ptr = myfn_malloc(size);
-
- if (!prevent_recursion)
+ if (!in_fprintf)
{
- struct timespec ts;
- ts.tv_sec = 0;
- ts.tv_nsec = 0;
-
- if (timestamp)
- clock_gettime(CLOCK_MONOTONIC, &ts);
-
- if (store)
- {
- if (cur_log == NULL || cur_log->n == 100)
- new_log_chunk();
-
- Log_entry* cur_entry = &cur_log->entries[cur_log->n];
-
- cur_entry->time = ts.tv_nsec;
- cur_entry->function = MALLOC;
- cur_entry->args[0] = (uintptr_t)size;
- cur_entry->args[1] = (uintptr_t)ptr;
- cur_log->n++;
- }
- else
- {
- prevent_recursion = 1;
- fprintf(out, "%lu %d ma %u %p\n", ts.tv_nsec, gettid(), size, ptr);
- prevent_recursion = 0;
- }
+ in_fprintf = 1;
+ fprintf(out, "%d\n", size);
+ in_fprintf = 0;
}
-
+ void *ptr = myfn_malloc(size);
return ptr;
}
-void free (void *ptr)
+void free(void *ptr)
{
- if (myfn_free == NULL)
+ // something wrong if we call free before one of the allocators!
+ if (myfn_malloc == NULL)
init();
if (!(ptr >= (void*) tmpbuff && ptr <= (void*)(tmpbuff + tmppos)))
- {
- if (!prevent_recursion)
- {
- struct timespec ts;
- ts.tv_sec = 0;
- ts.tv_nsec = 0;
-
- if (timestamp)
- clock_gettime(CLOCK_MONOTONIC, &ts);
-
- if (store)
- {
- if (cur_log == NULL || cur_log->n == 100)
- new_log_chunk();
-
- Log_entry* cur_entry = &cur_log->entries[cur_log->n];
-
- cur_entry->time = ts.tv_nsec;
- cur_entry->function = FREE;
- cur_entry->args[0] = (uintptr_t)ptr;
- cur_log->n++;
- }
- else
- {
- prevent_recursion = 1;
- fprintf(out, "%lu %d f %p\n", ts.tv_nsec, gettid(), ptr);
- prevent_recursion = 0;
- }
- }
-
myfn_free(ptr);
- }
}
-
-void *realloc (void *ptr, size_t size)
-{
- if (myfn_realloc == NULL)
- {
- void *nptr = malloc(size);
- if (nptr && ptr)
- {
- memmove(nptr, ptr, size);
- free(ptr);
- }
- return nptr;
- }
-
- void *nptr = myfn_realloc(ptr, size);
-
- if (!prevent_recursion)
- {
- struct timespec ts;
- ts.tv_sec = 0;
- ts.tv_nsec = 0;
-
- if (timestamp)
- clock_gettime(CLOCK_MONOTONIC, &ts);
-
- if (store)
- {
- if (cur_log == NULL || cur_log->n == 100)
- new_log_chunk();
-
- Log_entry* cur_entry = &cur_log->entries[cur_log->n];
-
- cur_entry->time = ts.tv_nsec;
- cur_entry->function = REALLOC;
- cur_entry->args[0] = (uintptr_t)ptr;
- cur_entry->args[1] = (uintptr_t)size;
- cur_entry->args[2] = (uintptr_t)nptr;
- cur_log->n++;
- }
- else
- {
- prevent_recursion = 1;
- fprintf(out, "%lu %d r %p %u %p\n", ts.tv_nsec, gettid(), ptr, size, nptr);
- prevent_recursion = 0;
- }
- }
-
- return nptr;
-}
-
-void *calloc (size_t nmemb, size_t size)
-{
- if (myfn_calloc == NULL)
- {
- void *ptr = malloc(nmemb*size);
- if (ptr)
- memset(ptr, 0, nmemb*size);
- return ptr;
- }
-
- void *ptr = myfn_calloc(nmemb, size);
-
- if (!prevent_recursion)
- {
- struct timespec ts;
- ts.tv_sec = 0;
- ts.tv_nsec = 0;
-
- if (timestamp)
- clock_gettime(CLOCK_MONOTONIC, &ts);
-
- if (store)
- {
- if (cur_log == NULL || cur_log->n == 100)
- new_log_chunk();
-
- Log_entry* cur_entry = &cur_log->entries[cur_log->n];
-
- cur_entry->time = ts.tv_nsec;
- cur_entry->function = CALLOC;
- cur_entry->args[0] = (uintptr_t)nmemb;
- cur_entry->args[1] = (uintptr_t)size;
- cur_entry->args[2] = (uintptr_t)ptr;
- cur_log->n++;
- }
- else
- {
- prevent_recursion = 1;
- fprintf(out, "%lu %d c %u %u %p\n", ts.tv_nsec, gettid(), nmemb, size, ptr);
- prevent_recursion = 0;
- }
- }
-
- return ptr;
-}
-
-void *memalign (size_t alignment, size_t size)
-{
- // Hopefully this gets never called during init()
- void *ptr = myfn_memalign(alignment, size);
-
- if (!prevent_recursion)
- {
- struct timespec ts;
- ts.tv_sec = 0;
- ts.tv_nsec = 0;
-
- if (timestamp)
- clock_gettime(CLOCK_MONOTONIC, &ts);
-
- if (store)
- {
- if (cur_log == NULL || cur_log->n == 100)
- new_log_chunk();
-
- Log_entry* cur_entry = &cur_log->entries[cur_log->n];
-
- cur_entry->time = ts.tv_nsec;
- cur_entry->function = MEMALIGN;
- cur_entry->args[0] = (uintptr_t)alignment;
- cur_entry->args[1] = (uintptr_t)size;
- cur_entry->args[2] = (uintptr_t)ptr;
- cur_log->n++;
- }
- else
- {
- prevent_recursion = 1;
- fprintf(out, "%lu %d mm %u %u %p\n", ts.tv_nsec, gettid(), alignment, size, ptr);
- prevent_recursion = 0;
- }
- }
-
- return ptr;
-}
-
generated by cgit v1.2.3 (git 2.25.1) at 2026-04-25 15:56:38 +0000