Libc-1244.1.7.tar.gz

[apple/libc.git] / gen / backtrace.c

diff --git a/gen/backtrace.c b/gen/backtrace.c
index d71143d76b79454bdedab1b3f7f7423ea59a8678..925dcb47bc0dfe301adb7e2f96ddb059a3e44a57 100644 (file)
--- a/gen/backtrace.c
+++ b/gen/backtrace.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2007 Apple Inc. All rights reserved.
+ * Copyright (c) 2007, 2008 Apple Inc. All rights reserved.
  *
  * @APPLE_LICENSE_HEADER_START@
  * 
@@ -25,6 +25,7 @@
 #include <sys/uio.h>
 
 #include <dlfcn.h>
+#include <stdint.h>
 #include <stdlib.h>
 #include <stdio.h>
 #include <string.h>
@@ -41,37 +42,49 @@ int backtrace(void** buffer, int size) {
 }
 
 #if __LP64__
-#define _BACKTRACE_FORMAT "%-4d%-35s 0x%016x %s + %u"
-#define _BACKTRACE_FORMAT_SIZE 82
+#define _BACKTRACE_FORMAT "%-4d%-35s 0x%016lx %s + %lu"
+#define _BACKTRACE_FORMAT_SIZE 83 /* %lu can take up to 20, does not include %s, includes NUL */
+#define _BACKTRACE_ADDRESS_LEN 18 /* 0x + 16 (no NUL) */
 #else
-#define _BACKTRACE_FORMAT "%-4d%-35s 0x%08x %s + %u"
-#define _BACKTRACE_FORMAT_SIZE 65
+#define _BACKTRACE_FORMAT "%-4d%-35s 0x%08lx %s + %lu"
+#define _BACKTRACE_FORMAT_SIZE 65 /* %lu can take up to 10, does not include %s, includes NUL */
+#define _BACKTRACE_ADDRESS_LEN 10 /* 0x + 8 (no NUL) */
 #endif
 
-
 static int _backtrace_snprintf(char* buf, size_t size, int frame, const void* addr, const Dl_info* info) {
-       char symbuf[19];
+       char symbuf[_BACKTRACE_ADDRESS_LEN + 1];
        const char* image = "???";
-       const char* symbol = symbuf;
+       const char* symbol = "0x0";
+       uintptr_t symbol_offset = 0;
 
        if (info->dli_fname) {
-               image = strrchr(info->dli_fname, '/') + 1;
-               if (image == NULL) image = info->dli_fname;
+               const char *tmp = strrchr(info->dli_fname, '/');
+               if(tmp == NULL)
+                       image = info->dli_fname;
+               else
+                       image = tmp + 1;
        }
        
        if (info->dli_sname) {
                symbol = info->dli_sname;
+               symbol_offset = (uintptr_t)addr - (uintptr_t)info->dli_saddr;
+       } else if(info->dli_fname) {
+               symbol = image;
+               symbol_offset = (uintptr_t)addr - (uintptr_t)info->dli_fbase;
+       } else if(0 < snprintf(symbuf, sizeof(symbuf), "0x%lx", (uintptr_t)info->dli_saddr)) {
+               symbol = symbuf;
+               symbol_offset = (uintptr_t)addr - (uintptr_t)info->dli_saddr;
        } else {
-               snprintf(symbuf, sizeof(symbuf), "0x%x", info->dli_saddr);
+               symbol_offset = (uintptr_t)addr;
        }
 
        return snprintf(buf, size,
                        _BACKTRACE_FORMAT,
                        frame,
                        image,
-                       addr,
+                       (uintptr_t)addr,
                        symbol,
-                       addr - info->dli_saddr) + 1;
+                       symbol_offset);
 }
 
 char** backtrace_symbols(void* const* buffer, int size) {
@@ -79,7 +92,7 @@ char** backtrace_symbols(void* const* buffer, int size) {
        size_t total_bytes;
        char** result;
        char** ptrs;
-       intptr_t strs;
+       intptr_t strs, end;
        Dl_info* info = calloc(size, sizeof (Dl_info));
        
        if (info == NULL) return NULL;
@@ -93,8 +106,18 @@ char** backtrace_symbols(void* const* buffer, int size) {
        // Plus each symbol description
        for (i = 0 ; i < size; ++i) {
                dladdr(buffer[i], &info[i]);
-               total_bytes += _BACKTRACE_FORMAT_SIZE + 1;
-               if (info[i].dli_sname) total_bytes += strlen(info[i].dli_sname);
+               total_bytes += _BACKTRACE_FORMAT_SIZE;
+               if (info[i].dli_sname) {
+                       total_bytes += strlen(info[i].dli_sname);
+               } else if(info[i].dli_fname) {
+                       const char *tmp = strrchr(info[i].dli_fname, '/');
+                       if(tmp == NULL)
+                               total_bytes += strlen(info[i].dli_fname);
+                       else
+                               total_bytes += strlen(tmp + 1);
+               } else {
+                       total_bytes += _BACKTRACE_ADDRESS_LEN;
+               }
        }
        
        result = (char**)malloc(total_bytes);
@@ -102,16 +125,24 @@ char** backtrace_symbols(void* const* buffer, int size) {
                free(info);
                return NULL;
        }
+       end = (intptr_t)result + total_bytes;
        
        // Fill in the array of pointers and append the strings for
        // each symbol description.
        
        ptrs = result;
        strs = ((intptr_t)result) + sizeof(char*) * size;
-       
+
        for (i = 0; i < size; ++i) {
+               int chk = _backtrace_snprintf((char*)strs, end - (intptr_t)strs, i, buffer[i], &info[i]);
+
+               if(chk < 0) {
+                       free(info);
+                       return NULL;
+               }
+
                ptrs[i] = (char*)strs;
-               strs += _backtrace_snprintf((char*)strs, total_bytes, i, buffer[i], &info[i]);
+               strs += chk + 1; // Step over the '\0'
        }
        
        free(info);