lib/util/talloc_report.c

   1 /*
   2  * talloc_report into a string
   3  *
   4  * Copyright Volker Lendecke <vl@samba.org> 2015
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 3 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  18  */
  19
  20 #include "replace.h"
  21 #include "talloc_report.h"
  22
  23 /*
  24  * talloc_vasprintf into a buffer that doubles its size. The real string
  25  * length is maintained in "pstr_len".
  26  */
  27
  28 static char *talloc_vasprintf_append_largebuf(char *buf, ssize_t *pstr_len,
  29                                               const char *fmt, va_list ap)
  30                                               PRINTF_ATTRIBUTE(3,0);
  31
  32 static char *talloc_vasprintf_append_largebuf(char *buf, ssize_t *pstr_len,
  33                                               const char *fmt, va_list ap)
  34 {
  35         ssize_t str_len = *pstr_len;
  36         size_t buflen, needed, space = 0;
  37         char *start = NULL, *tmpbuf = NULL;
  38         va_list ap2;
  39         int printlen;
  40
  41         if (str_len == -1) {
  42                 return NULL;
  43         }
  44         if (buf == NULL) {
  45                 return NULL;
  46         }
  47         if (fmt == NULL) {
  48                 return NULL;
  49         }
  50         buflen = talloc_get_size(buf);
  51
  52         if (buflen > str_len) {
  53                 start = buf + str_len;
  54                 space = buflen - str_len;
  55         }
  56
  57         va_copy(ap2, ap);
  58         printlen = vsnprintf(start, space, fmt, ap2);
  59         va_end(ap2);
  60
  61         if (printlen < 0) {
  62                 goto fail;
  63         }
  64
  65         needed = str_len + printlen + 1;
  66
  67         if (needed > buflen) {
  68                 buflen = MAX(128, buflen);
  69
  70                 while (buflen < needed) {
  71                         buflen *= 2;
  72                 }
  73
  74                 tmpbuf = talloc_realloc(NULL, buf, char, buflen);
  75                 if (tmpbuf == NULL) {
  76                         goto fail;
  77                 }
  78                 buf = tmpbuf;
  79
  80                 va_copy(ap2, ap);
  81                 vsnprintf(buf + str_len, buflen - str_len, fmt, ap2);
  82                 va_end(ap2);
  83         }
  84         *pstr_len = (needed - 1);
  85         return buf;
  86 fail:
  87         *pstr_len = -1;
  88         return buf;
  89 }
  90
  91 static char *talloc_asprintf_append_largebuf(char *buf, ssize_t *pstr_len,
  92                                              const char *fmt, ...)
  93                                              PRINTF_ATTRIBUTE(3,4);
  94
  95 static char *talloc_asprintf_append_largebuf(char *buf, ssize_t *pstr_len,
  96                                              const char *fmt, ...)
  97 {
  98         va_list ap;
  99
 100         va_start(ap, fmt);
 101         buf = talloc_vasprintf_append_largebuf(buf, pstr_len, fmt, ap);
 102         va_end(ap);
 103         return buf;
 104 }
 105
 106 struct talloc_report_str_state {
 107         ssize_t str_len;
 108         char *s;
 109 };
 110
 111 static void talloc_report_str_helper(const void *ptr, int depth, int max_depth,
 112                                      int is_ref, void *private_data)
 113 {
 114         struct talloc_report_str_state *state = private_data;
 115         const char *name = talloc_get_name(ptr);
 116
 117         if (ptr == state->s) {
 118                 return;
 119         }
 120
 121         if (is_ref) {
 122                 state->s = talloc_asprintf_append_largebuf(
 123                         state->s, &state->str_len,
 124                         "%*sreference to: %s\n", depth*4, "", name);
 125                 return;
 126         }
 127
 128         if (depth == 0) {
 129                 state->s = talloc_asprintf_append_largebuf(
 130                         state->s, &state->str_len,
 131                         "%stalloc report on '%s' "
 132                         "(total %6lu bytes in %3lu blocks)\n",
 133                         (max_depth < 0 ? "full " :""), name,
 134                         (unsigned long)talloc_total_size(ptr),
 135                         (unsigned long)talloc_total_blocks(ptr));
 136                 return;
 137         }
 138
 139         if (strcmp(name, "char") == 0) {
 140                 /*
 141                  * Print out the first 50 bytes of the string
 142                  */
 143                 state->s = talloc_asprintf_append_largebuf(
 144                         state->s, &state->str_len,
 145                         "%*s%-30s contains %6lu bytes in %3lu blocks "
 146                         "(ref %zu): %*s\n", depth*4, "", name,
 147                         (unsigned long)talloc_total_size(ptr),
 148                         (unsigned long)talloc_total_blocks(ptr),
 149                         talloc_reference_count(ptr),
 150                         (int)MIN(50, talloc_get_size(ptr)),
 151                         (const char *)ptr);
 152                 return;
 153         }
 154
 155         state->s = talloc_asprintf_append_largebuf(
 156                 state->s, &state->str_len,
 157                 "%*s%-30s contains %6lu bytes in %3lu blocks (ref %zu) %p\n",
 158                 depth*4, "", name,
 159                 (unsigned long)talloc_total_size(ptr),
 160                 (unsigned long)talloc_total_blocks(ptr),
 161                 talloc_reference_count(ptr), ptr);
 162 }
 163
 164 char *talloc_report_str(TALLOC_CTX *mem_ctx, TALLOC_CTX *root)
 165 {
 166         struct talloc_report_str_state state;
 167
 168         state.s = talloc_strdup(mem_ctx, "");
 169         if (state.s == NULL) {
 170                 return NULL;
 171         }
 172         state.str_len = 0;
 173
 174         talloc_report_depth_cb(root, 0, -1, talloc_report_str_helper, &state);
 175
 176         if (state.str_len == -1) {
 177                 talloc_free(state.s);
 178                 return NULL;
 179         }
 180
 181         return talloc_realloc(mem_ctx, state.s, char, state.str_len+1);
 182 }