内存泄漏/ GLib问题

1: /* 2: * File: xyn-playlist.c 3: * Author: Andrei Ciobanu 4: * 5: * Created on June 4, 2010, 12:47 PM 6: */ 7:  8: #include  9: #include  10: #include  11: #include  12: #include  13: #include  14:  15: /** 16: * Returns a list all the file(paths) from a directory. 17: * Returns 'NULL' if a certain error occurs. 18: * @param dir_path. 19: * @param A list of gchars* indicating what file patterns to detect. 20: */ 21: GSList *xyn_pl_get_files(const gchar *dir_path, GSList *file_patterns) { 22: /* Returning list containing file paths */ 23: GSList *fpaths = NULL; 24: /* Used to scan directories for subdirs. Acts like a 25: * stack, to avoid recursion. */ 26: GSList *dirs = NULL; 27: /* Current dir */ 28: DIR *cdir = NULL; 29: /* Current dir entries */ 30: struct dirent *cent = NULL; 31: /* File stats */ 32: struct stat cent_stat; 33: /* dir_path duplicate, on the heap */ 34: gchar *dir_pdup; 35:  36: if (dir_path == NULL) { 37: return NULL; 38: } 39:  40: dir_pdup = g_strdup((const gchar*) dir_path); 41: dirs = g_slist_append(dirs, (gpointer) dir_pdup); 42: while (dirs != NULL) { 43: cdir = opendir((const gchar*) dirs->data); 44: if (cdir == NULL) { 45: g_slist_free(dirs); 46: g_slist_free(fpaths); 47: return NULL; 48: } 49: chdir((const gchar*) dirs->data); 50: while ((cent = readdir(cdir)) != NULL) { 51: lstat(cent->d_name, &cent_stat); 52: if (S_ISDIR(cent_stat.st_mode)) { 53: if (g_strcmp0(cent->d_name, ".") == 0 || 54: g_strcmp0(cent->d_name, "..") == 0) { 55: /* Skip "." and ".." dirs */ 56: continue; 57: } 58: dirs = g_slist_append(dirs, 59: g_strconcat((gchar*) dirs->data, "/", cent->d_name, NULL)); 60: } else { 61: fpaths = g_slist_append(fpaths, 62: g_strconcat((gchar*) dirs->data, "/", cent->d_name, NULL)); 63: } 64: } 65: g_free(dirs->data); 66: dirs = g_slist_delete_link(dirs, dirs); 67: closedir(cdir); 68: } 69: return fpaths; 70: } 71:  72: int main(int argc, char** argv) { 73: GSList *l = NULL; 74: l = xyn_pl_get_files("/home/andrei/Music", NULL); 75: g_slist_foreach(l,(GFunc)printf,NULL); 76: printf("%d\n",g_slist_length(l)); 77: g_slist_free(l); 78: return (0); 79: } 80:  81:  82: -----------------------------------------------------------------------------------------------==15429== 83: ==15429== HEAP SUMMARY: 84: ==15429== in use at exit: 751,451 bytes in 7,263 blocks 85: ==15429== total heap usage: 8,611 allocs, 1,348 frees, 22,898,217 bytes allocated 86: ==15429== 87: ==15429== 120 bytes in 1 blocks are possibly lost in loss record 1 of 11 88: ==15429== at 0x4024106: memalign (vg_replace_malloc.c:581) 89: ==15429== by 0x4024163: posix_memalign (vg_replace_malloc.c:709) 90: ==15429== by 0x40969C1: ??? (in /lib/libglib-2.0.so.0.2400.1) 91: ==15429== by 0x40971F6: g_slice_alloc (in /lib/libglib-2.0.so.0.2400.1) 92: ==15429== by 0x40988A5: g_slist_append (in /lib/libglib-2.0.so.0.2400.1) 93: ==15429== by 0x80488F0: xyn_pl_get_files (xyn-playlist.c:41) 94: ==15429== by 0x8048848: main (main.c:18) 95: ==15429== 96: ==15429== 129 bytes in 1 blocks are possibly lost in loss record 2 of 11 97: ==15429== at 0x4024F20: malloc (vg_replace_malloc.c:236) 98: ==15429== by 0x4081243: g_malloc (in /lib/libglib-2.0.so.0.2400.1) 99: ==15429== by 0x409B85B: g_strconcat (in /lib/libglib-2.0.so.0.2400.1) 100: ==15429== by 0x80489FE: xyn_pl_get_files (xyn-playlist.c:62) 101: ==15429== by 0x8048848: main (main.c:18) 102: ==15429== 103: ==15429== 360 bytes in 3 blocks are possibly lost in loss record 3 of 11 104: ==15429== at 0x4024106: memalign (vg_replace_malloc.c:581) 105: ==15429== by 0x4024163: posix_memalign (vg_replace_malloc.c:709) 106: ==15429== by 0x40969C1: ??? (in /lib/libglib-2.0.so.0.2400.1) 107: ==15429== by 0x4097222: g_slice_alloc (in /lib/libglib-2.0.so.0.2400.1) 108: ==15429== by 0x40988A5: g_slist_append (in /lib/libglib-2.0.so.0.2400.1) 109: ==15429== by 0x80488F0: xyn_pl_get_files (xyn-playlist.c:41) 110: ==15429== by 0x8048848: main (main.c:18) 111: ==15429== 112: ==15429== 508 bytes in 1 blocks are still reachable in loss record 4 of 11 113: ==15429== at 0x402425F: calloc (vg_replace_malloc.c:467) 114: ==15429== by 0x408113B: g_malloc0 (in /lib/libglib-2.0.so.0.2400.1) 115: ==15429== by 0x409624D: ??? (in /lib/libglib-2.0.so.0.2400.1) 116: ==15429== by 0x409710C: g_slice_alloc (in /lib/libglib-2.0.so.0.2400.1) 117: ==15429== by 0x40988A5: g_slist_append (in /lib/libglib-2.0.so.0.2400.1) 118: ==15429== by 0x80488F0: xyn_pl_get_files (xyn-playlist.c:41) 119: ==15429== by 0x8048848: main (main.c:18) 120: ==15429== 121: ==15429== 508 bytes in 1 blocks are still reachable in loss record 5 of 11 122: ==15429== at 0x402425F: calloc (vg_replace_malloc.c:467) 123: ==15429== by 0x408113B: g_malloc0 (in /lib/libglib-2.0.so.0.2400.1) 124: ==15429== by 0x409626F: ??? (in /lib/libglib-2.0.so.0.2400.1) 125: ==15429== by 0x409710C: g_slice_alloc (in /lib/libglib-2.0.so.0.2400.1) 126: ==15429== by 0x40988A5: g_slist_append (in /lib/libglib-2.0.so.0.2400.1) 127: ==15429== by 0x80488F0: xyn_pl_get_files (xyn-playlist.c:41) 128: ==15429== by 0x8048848: main (main.c:18) 129: ==15429== 130: ==15429== 508 bytes in 1 blocks are still reachable in loss record 6 of 11 131: ==15429== at 0x402425F: calloc (vg_replace_malloc.c:467) 132: ==15429== by 0x408113B: g_malloc0 (in /lib/libglib-2.0.so.0.2400.1) 133: ==15429== by 0x4096291: ??? (in /lib/libglib-2.0.so.0.2400.1) 134: ==15429== by 0x409710C: g_slice_alloc (in /lib/libglib-2.0.so.0.2400.1) 135: ==15429== by 0x40988A5: g_slist_append (in /lib/libglib-2.0.so.0.2400.1) 136: ==15429== by 0x80488F0: xyn_pl_get_files (xyn-playlist.c:41) 137: ==15429== by 0x8048848: main (main.c:18) 138: ==15429== 139: ==15429== 1,200 bytes in 10 blocks are possibly lost in loss record 7 of 11 140: ==15429== at 0x4024106: memalign (vg_replace_malloc.c:581) 141: ==15429== by 0x4024163: posix_memalign (vg_replace_malloc.c:709) 142: ==15429== by 0x40969C1: ??? (in /lib/libglib-2.0.so.0.2400.1) 143: ==15429== by 0x40971F6: g_slice_alloc (in /lib/libglib-2.0.so.0.2400.1) 144: ==15429== by 0x40988A5: g_slist_append (in /lib/libglib-2.0.so.0.2400.1) 145: ==15429== by 0x8048A0D: xyn_pl_get_files (xyn-playlist.c:61) 146: ==15429== by 0x8048848: main (main.c:18) 147: ==15429== 148: ==15429== 2,040 bytes in 1 blocks are still reachable in loss record 8 of 11 149: ==15429== at 0x402425F: calloc (vg_replace_malloc.c:467) 150: ==15429== by 0x408113B: g_malloc0 (in /lib/libglib-2.0.so.0.2400.1) 151: ==15429== by 0x40970AB: g_slice_alloc (in /lib/libglib-2.0.so.0.2400.1) 152: ==15429== by 0x40988A5: g_slist_append (in /lib/libglib-2.0.so.0.2400.1) 153: ==15429== by 0x80488F0: xyn_pl_get_files (xyn-playlist.c:41) 154: ==15429== by 0x8048848: main (main.c:18) 155: ==15429== 156: ==15429== 4,320 bytes in 36 blocks are possibly lost in loss record 9 of 11 157: ==15429== at 0x4024106: memalign (vg_replace_malloc.c:581) 158: ==15429== by 0x4024163: posix_memalign (vg_replace_malloc.c:709) 159: ==15429== by 0x40969C1: ??? (in /lib/libglib-2.0.so.0.2400.1) 160: ==15429== by 0x4097222: g_slice_alloc (in /lib/libglib-2.0.so.0.2400.1) 161: ==15429== by 0x40988A5: g_slist_append (in /lib/libglib-2.0.so.0.2400.1) 162: ==15429== by 0x80489D2: xyn_pl_get_files (xyn-playlist.c:58) 163: ==15429== by 0x8048848: main (main.c:18) 164: ==15429== 165: ==15429== 56,640 bytes in 472 blocks are possibly lost in loss record 10 of 11 166: ==15429== at 0x4024106: memalign (vg_replace_malloc.c:581) 167: ==15429== by 0x4024163: posix_memalign (vg_replace_malloc.c:709) 168: ==15429== by 0x40969C1: ??? (in /lib/libglib-2.0.so.0.2400.1) 169: ==15429== by 0x4097222: g_slice_alloc (in /lib/libglib-2.0.so.0.2400.1) 170: ==15429== by 0x40988A5: g_slist_append (in /lib/libglib-2.0.so.0.2400.1) 171: ==15429== by 0x8048A0D: xyn_pl_get_files (xyn-playlist.c:61) 172: ==15429== by 0x8048848: main (main.c:18) 173: ==15429== 174: ==15429== 685,118 bytes in 6,736 blocks are definitely lost in loss record 11 of 11 175: ==15429== at 0x4024F20: malloc (vg_replace_malloc.c:236) 176: ==15429== by 0x4081243: g_malloc (in /lib/libglib-2.0.so.0.2400.1) 177: ==15429== by 0x409B85B: g_strconcat (in /lib/libglib-2.0.so.0.2400.1) 178: ==15429== by 0x80489FE: xyn_pl_get_files (xyn-playlist.c:62) 179: ==15429== by 0x8048848: main (main.c:18) 180: ==15429== 181: ==15429== LEAK SUMMARY: 182: ==15429== definitely lost: 685,118 bytes in 6,736 blocks 183: ==15429== indirectly lost: 0 bytes in 0 blocks 184: ==15429== possibly lost: 62,769 bytes in 523 blocks 185: ==15429== still reachable: 3,564 bytes in 4 blocks 186: ==15429== suppressed: 0 bytes in 0 blocks 187: ==15429== 188: ==15429== For counts of detected and suppressed errors, rerun with: -v 189: ==15429== ERROR SUMMARY: 7 errors from 7 contexts (suppressed: 17 from 8) 190: ---------------------------------------------------------------------------------------------- 

我使用上面的代码来创建一个包含特定目录中所有文件路径的列表。 (在我的情况下, fts.hftw.h不是一个选项)。

我使用GLib作为数据结构库。 关于GLib分配,解除分配内存的方式,我还有疑问吗?

当调用g_slist_free(list)时,我还释放元素包含的数据? 为什么会出现所有这些内存泄漏? 在使用像GLib这样的复杂库时,valgrind是用于profilinf内存问题的合适工具吗?

后期编辑:

如果我g_slist_foreach(l,(GFunc)g_free,NULL); ,valgrind的报告是不同的,(’绝对丢失’的所有内存泄漏将转移到’间接丢失’)。 我还没有看到这一点? GLib集合不是实现了一种被释放的方式吗?

不, g_slist_free不会释放您存储在列表中的数据(例如字符串)。 它无法知道您是否以及如何释放此数据。 您可以将相同的指针存储在多个列表中。 此外,您可以在列表中存储非指针类型,或者不使用malloc分配的类型。 该集合不允许您提供析构函数。 因此,您需要在释放列表之前循环并释放数据。

此外, g_slist可以使用内存池,因此valgrind可能无法始终提供正确的结果。

其他类型(如GPtrArray )允许您为元素数据提供析构函数( GDestroyNotify )。