xref: /third_party/curl/lib/memdebug.c (revision 13498266)
1/***************************************************************************
2 *                                  _   _ ____  _
3 *  Project                     ___| | | |  _ \| |
4 *                             / __| | | | |_) | |
5 *                            | (__| |_| |  _ <| |___
6 *                             \___|\___/|_| \_\_____|
7 *
8 * Copyright (C) Daniel Stenberg, <daniel@haxx.se>, et al.
9 *
10 * This software is licensed as described in the file COPYING, which
11 * you should have received as part of this distribution. The terms
12 * are also available at https://curl.se/docs/copyright.html.
13 *
14 * You may opt to use, copy, modify, merge, publish, distribute and/or sell
15 * copies of the Software, and permit persons to whom the Software is
16 * furnished to do so, under the terms of the COPYING file.
17 *
18 * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
19 * KIND, either express or implied.
20 *
21 * SPDX-License-Identifier: curl
22 *
23 ***************************************************************************/
24
25#include "curl_setup.h"
26
27#ifdef CURLDEBUG
28
29#include <curl/curl.h>
30
31#include "urldata.h"
32
33#define MEMDEBUG_NODEFINES /* don't redefine the standard functions */
34
35/* The last 3 #include files should be in this order */
36#include "curl_printf.h"
37#include "curl_memory.h"
38#include "memdebug.h"
39
40struct memdebug {
41  size_t size;
42  union {
43    curl_off_t o;
44    double d;
45    void *p;
46  } mem[1];
47  /* I'm hoping this is the thing with the strictest alignment
48   * requirements.  That also means we waste some space :-( */
49};
50
51/*
52 * Note that these debug functions are very simple and they are meant to
53 * remain so. For advanced analysis, record a log file and write perl scripts
54 * to analyze them!
55 *
56 * Don't use these with multithreaded test programs!
57 */
58
59FILE *curl_dbg_logfile = NULL;
60static bool registered_cleanup = FALSE; /* atexit registered cleanup */
61static bool memlimit = FALSE; /* enable memory limit */
62static long memsize = 0;  /* set number of mallocs allowed */
63
64/* LeakSantizier (LSAN) calls _exit() instead of exit() when a leak is detected
65   on exit so the logfile must be closed explicitly or data could be lost.
66   Though _exit() does not call atexit handlers such as this, LSAN's call to
67   _exit() comes after the atexit handlers are called. curl/curl#6620 */
68static void curl_dbg_cleanup(void)
69{
70  if(curl_dbg_logfile &&
71     curl_dbg_logfile != stderr &&
72     curl_dbg_logfile != stdout) {
73    fclose(curl_dbg_logfile);
74  }
75  curl_dbg_logfile = NULL;
76}
77
78/* this sets the log file name */
79void curl_dbg_memdebug(const char *logname)
80{
81  if(!curl_dbg_logfile) {
82    if(logname && *logname)
83      curl_dbg_logfile = fopen(logname, FOPEN_WRITETEXT);
84    else
85      curl_dbg_logfile = stderr;
86#ifdef MEMDEBUG_LOG_SYNC
87    /* Flush the log file after every line so the log isn't lost in a crash */
88    if(curl_dbg_logfile)
89      setbuf(curl_dbg_logfile, (char *)NULL);
90#endif
91  }
92  if(!registered_cleanup)
93    registered_cleanup = !atexit(curl_dbg_cleanup);
94}
95
96/* This function sets the number of malloc() calls that should return
97   successfully! */
98void curl_dbg_memlimit(long limit)
99{
100  if(!memlimit) {
101    memlimit = TRUE;
102    memsize = limit;
103  }
104}
105
106/* returns TRUE if this isn't allowed! */
107static bool countcheck(const char *func, int line, const char *source)
108{
109  /* if source is NULL, then the call is made internally and this check
110     should not be made */
111  if(memlimit && source) {
112    if(!memsize) {
113      /* log to file */
114      curl_dbg_log("LIMIT %s:%d %s reached memlimit\n",
115                   source, line, func);
116      /* log to stderr also */
117      fprintf(stderr, "LIMIT %s:%d %s reached memlimit\n",
118              source, line, func);
119      fflush(curl_dbg_logfile); /* because it might crash now */
120      errno = ENOMEM;
121      return TRUE; /* RETURN ERROR! */
122    }
123    else
124      memsize--; /* countdown */
125
126
127  }
128
129  return FALSE; /* allow this */
130}
131
132ALLOC_FUNC void *curl_dbg_malloc(size_t wantedsize,
133                                 int line, const char *source)
134{
135  struct memdebug *mem;
136  size_t size;
137
138  DEBUGASSERT(wantedsize != 0);
139
140  if(countcheck("malloc", line, source))
141    return NULL;
142
143  /* alloc at least 64 bytes */
144  size = sizeof(struct memdebug) + wantedsize;
145
146  mem = (Curl_cmalloc)(size);
147  if(mem) {
148    mem->size = wantedsize;
149  }
150
151  if(source)
152    curl_dbg_log("MEM %s:%d malloc(%zu) = %p\n",
153                 source, line, wantedsize,
154                 mem ? (void *)mem->mem : (void *)0);
155
156  return (mem ? mem->mem : NULL);
157}
158
159ALLOC_FUNC void *curl_dbg_calloc(size_t wanted_elements, size_t wanted_size,
160                                 int line, const char *source)
161{
162  struct memdebug *mem;
163  size_t size, user_size;
164
165  DEBUGASSERT(wanted_elements != 0);
166  DEBUGASSERT(wanted_size != 0);
167
168  if(countcheck("calloc", line, source))
169    return NULL;
170
171  /* alloc at least 64 bytes */
172  user_size = wanted_size * wanted_elements;
173  size = sizeof(struct memdebug) + user_size;
174
175  mem = (Curl_ccalloc)(1, size);
176  if(mem)
177    mem->size = user_size;
178
179  if(source)
180    curl_dbg_log("MEM %s:%d calloc(%zu,%zu) = %p\n",
181                 source, line, wanted_elements, wanted_size,
182                 mem ? (void *)mem->mem : (void *)0);
183
184  return (mem ? mem->mem : NULL);
185}
186
187ALLOC_FUNC char *curl_dbg_strdup(const char *str,
188                                 int line, const char *source)
189{
190  char *mem;
191  size_t len;
192
193  DEBUGASSERT(str != NULL);
194
195  if(countcheck("strdup", line, source))
196    return NULL;
197
198  len = strlen(str) + 1;
199
200  mem = curl_dbg_malloc(len, 0, NULL); /* NULL prevents logging */
201  if(mem)
202    memcpy(mem, str, len);
203
204  if(source)
205    curl_dbg_log("MEM %s:%d strdup(%p) (%zu) = %p\n",
206                 source, line, (const void *)str, len, (const void *)mem);
207
208  return mem;
209}
210
211#if defined(_WIN32) && defined(UNICODE)
212ALLOC_FUNC wchar_t *curl_dbg_wcsdup(const wchar_t *str,
213                                    int line, const char *source)
214{
215  wchar_t *mem;
216  size_t wsiz, bsiz;
217
218  DEBUGASSERT(str != NULL);
219
220  if(countcheck("wcsdup", line, source))
221    return NULL;
222
223  wsiz = wcslen(str) + 1;
224  bsiz = wsiz * sizeof(wchar_t);
225
226  mem = curl_dbg_malloc(bsiz, 0, NULL); /* NULL prevents logging */
227  if(mem)
228    memcpy(mem, str, bsiz);
229
230  if(source)
231    curl_dbg_log("MEM %s:%d wcsdup(%p) (%zu) = %p\n",
232                source, line, (void *)str, bsiz, (void *)mem);
233
234  return mem;
235}
236#endif
237
238/* We provide a realloc() that accepts a NULL as pointer, which then
239   performs a malloc(). In order to work with ares. */
240void *curl_dbg_realloc(void *ptr, size_t wantedsize,
241                      int line, const char *source)
242{
243  struct memdebug *mem = NULL;
244
245  size_t size = sizeof(struct memdebug) + wantedsize;
246
247  DEBUGASSERT(wantedsize != 0);
248
249  if(countcheck("realloc", line, source))
250    return NULL;
251
252#ifdef __INTEL_COMPILER
253#  pragma warning(push)
254#  pragma warning(disable:1684)
255   /* 1684: conversion from pointer to same-sized integral type */
256#endif
257
258  if(ptr)
259    mem = (void *)((char *)ptr - offsetof(struct memdebug, mem));
260
261#ifdef __INTEL_COMPILER
262#  pragma warning(pop)
263#endif
264
265  mem = (Curl_crealloc)(mem, size);
266  if(source)
267    curl_dbg_log("MEM %s:%d realloc(%p, %zu) = %p\n",
268                source, line, (void *)ptr, wantedsize,
269                mem ? (void *)mem->mem : (void *)0);
270
271  if(mem) {
272    mem->size = wantedsize;
273    return mem->mem;
274  }
275
276  return NULL;
277}
278
279void curl_dbg_free(void *ptr, int line, const char *source)
280{
281  if(ptr) {
282    struct memdebug *mem;
283
284#ifdef __INTEL_COMPILER
285#  pragma warning(push)
286#  pragma warning(disable:1684)
287   /* 1684: conversion from pointer to same-sized integral type */
288#endif
289
290    mem = (void *)((char *)ptr - offsetof(struct memdebug, mem));
291
292#ifdef __INTEL_COMPILER
293#  pragma warning(pop)
294#endif
295
296    /* free for real */
297    (Curl_cfree)(mem);
298  }
299
300  if(source && ptr)
301    curl_dbg_log("MEM %s:%d free(%p)\n", source, line, (void *)ptr);
302}
303
304curl_socket_t curl_dbg_socket(int domain, int type, int protocol,
305                             int line, const char *source)
306{
307  curl_socket_t sockfd;
308
309  if(countcheck("socket", line, source))
310    return CURL_SOCKET_BAD;
311
312  sockfd = socket(domain, type, protocol);
313
314  if(source && (sockfd != CURL_SOCKET_BAD))
315    curl_dbg_log("FD %s:%d socket() = %" CURL_FORMAT_SOCKET_T "\n",
316                 source, line, sockfd);
317
318  return sockfd;
319}
320
321SEND_TYPE_RETV curl_dbg_send(SEND_TYPE_ARG1 sockfd,
322                            SEND_QUAL_ARG2 SEND_TYPE_ARG2 buf,
323                            SEND_TYPE_ARG3 len, SEND_TYPE_ARG4 flags, int line,
324                            const char *source)
325{
326  SEND_TYPE_RETV rc;
327  if(countcheck("send", line, source))
328    return -1;
329  rc = send(sockfd, buf, len, flags);
330  if(source)
331    curl_dbg_log("SEND %s:%d send(%lu) = %ld\n",
332                source, line, (unsigned long)len, (long)rc);
333  return rc;
334}
335
336RECV_TYPE_RETV curl_dbg_recv(RECV_TYPE_ARG1 sockfd, RECV_TYPE_ARG2 buf,
337                            RECV_TYPE_ARG3 len, RECV_TYPE_ARG4 flags, int line,
338                            const char *source)
339{
340  RECV_TYPE_RETV rc;
341  if(countcheck("recv", line, source))
342    return -1;
343  rc = recv(sockfd, buf, len, flags);
344  if(source)
345    curl_dbg_log("RECV %s:%d recv(%lu) = %ld\n",
346                source, line, (unsigned long)len, (long)rc);
347  return rc;
348}
349
350#ifdef HAVE_SOCKETPAIR
351int curl_dbg_socketpair(int domain, int type, int protocol,
352                       curl_socket_t socket_vector[2],
353                       int line, const char *source)
354{
355  int res = socketpair(domain, type, protocol, socket_vector);
356
357  if(source && (0 == res))
358    curl_dbg_log("FD %s:%d socketpair() = "
359      "%" CURL_FORMAT_SOCKET_T " %" CURL_FORMAT_SOCKET_T "\n",
360      source, line, socket_vector[0], socket_vector[1]);
361
362  return res;
363}
364#endif
365
366curl_socket_t curl_dbg_accept(curl_socket_t s, void *saddr, void *saddrlen,
367                             int line, const char *source)
368{
369  struct sockaddr *addr = (struct sockaddr *)saddr;
370  curl_socklen_t *addrlen = (curl_socklen_t *)saddrlen;
371
372  curl_socket_t sockfd = accept(s, addr, addrlen);
373
374  if(source && (sockfd != CURL_SOCKET_BAD))
375    curl_dbg_log("FD %s:%d accept() = %" CURL_FORMAT_SOCKET_T "\n",
376                 source, line, sockfd);
377
378  return sockfd;
379}
380
381/* separate function to allow libcurl to mark a "faked" close */
382void curl_dbg_mark_sclose(curl_socket_t sockfd, int line, const char *source)
383{
384  if(source)
385    curl_dbg_log("FD %s:%d sclose(%" CURL_FORMAT_SOCKET_T ")\n",
386                 source, line, sockfd);
387}
388
389/* this is our own defined way to close sockets on *ALL* platforms */
390int curl_dbg_sclose(curl_socket_t sockfd, int line, const char *source)
391{
392  int res = sclose(sockfd);
393  curl_dbg_mark_sclose(sockfd, line, source);
394  return res;
395}
396
397ALLOC_FUNC FILE *curl_dbg_fopen(const char *file, const char *mode,
398                                int line, const char *source)
399{
400  FILE *res = fopen(file, mode);
401
402  if(source)
403    curl_dbg_log("FILE %s:%d fopen(\"%s\",\"%s\") = %p\n",
404                source, line, file, mode, (void *)res);
405
406  return res;
407}
408
409ALLOC_FUNC FILE *curl_dbg_fdopen(int filedes, const char *mode,
410                                 int line, const char *source)
411{
412  FILE *res = fdopen(filedes, mode);
413  if(source)
414    curl_dbg_log("FILE %s:%d fdopen(\"%d\",\"%s\") = %p\n",
415                 source, line, filedes, mode, (void *)res);
416  return res;
417}
418
419int curl_dbg_fclose(FILE *file, int line, const char *source)
420{
421  int res;
422
423  DEBUGASSERT(file != NULL);
424
425  if(source)
426    curl_dbg_log("FILE %s:%d fclose(%p)\n",
427                 source, line, (void *)file);
428
429  res = fclose(file);
430
431  return res;
432}
433
434#define LOGLINE_BUFSIZE  1024
435
436/* this does the writing to the memory tracking log file */
437void curl_dbg_log(const char *format, ...)
438{
439  char *buf;
440  int nchars;
441  va_list ap;
442
443  if(!curl_dbg_logfile)
444    return;
445
446  buf = (Curl_cmalloc)(LOGLINE_BUFSIZE);
447  if(!buf)
448    return;
449
450  va_start(ap, format);
451  nchars = mvsnprintf(buf, LOGLINE_BUFSIZE, format, ap);
452  va_end(ap);
453
454  if(nchars > LOGLINE_BUFSIZE - 1)
455    nchars = LOGLINE_BUFSIZE - 1;
456
457  if(nchars > 0)
458    fwrite(buf, 1, (size_t)nchars, curl_dbg_logfile);
459
460  (Curl_cfree)(buf);
461}
462
463#endif /* CURLDEBUG */
464