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 > (size_t)str_len) {
  53                 start = buf + str_len;
  54                 space = buflen - str_len;
  55         } else {
  56                 return NULL;
  57         }
  58
  59         va_copy(ap2, ap);
  60         printlen = vsnprintf(start, space, fmt, ap2);
  61         va_end(ap2);
  62
  63         if (printlen < 0) {
  64                 goto fail;
  65         }
  66
  67         needed = str_len + printlen + 1;
  68
  69         if (needed > buflen) {
  70                 buflen = MAX(128, buflen);
  71
  72                 while (buflen < needed) {
  73                         buflen *= 2;
  74                 }
  75
  76                 tmpbuf = talloc_realloc(NULL, buf, char, buflen);
  77                 if (tmpbuf == NULL) {
  78                         goto fail;
  79                 }
  80                 buf = tmpbuf;
  81
  82                 va_copy(ap2, ap);
  83                 vsnprintf(buf + str_len, buflen - str_len, fmt, ap2);
  84                 va_end(ap2);
  85         }
  86         *pstr_len = (needed - 1);
  87         return buf;
  88 fail:
  89         *pstr_len = -1;
  90         return buf;
  91 }
  92
  93 static char *talloc_asprintf_append_largebuf(char *buf, ssize_t *pstr_len,
  94                                              const char *fmt, ...)
  95                                              PRINTF_ATTRIBUTE(3,4);
  96
  97 static char *talloc_asprintf_append_largebuf(char *buf, ssize_t *pstr_len,
  98                                              const char *fmt, ...)
  99 {
 100         va_list ap;
 101
 102         va_start(ap, fmt);
 103         buf = talloc_vasprintf_append_largebuf(buf, pstr_len, fmt, ap);
 104         va_end(ap);
 105         return buf;
 106 }
 107
 108 struct talloc_report_str_state {
 109         ssize_t str_len;
 110         char *s;
 111 };
 112
 113 static void talloc_report_str_helper(const void *ptr, int depth, int max_depth,
 114                                      int is_ref, void *private_data)
 115 {
 116         struct talloc_report_str_state *state = private_data;
 117         const char *name = talloc_get_name(ptr);
 118
 119         if (ptr == state->s) {
 120                 return;
 121         }
 122
 123         if (is_ref) {
 124                 state->s = talloc_asprintf_append_largebuf(
 125                         state->s, &state->str_len,
 126                         "%*sreference to: %s\n", depth*4, "", name);
 127                 return;
 128         }
 129
 130         if (depth == 0) {
 131                 state->s = talloc_asprintf_append_largebuf(
 132                         state->s, &state->str_len,
 133                         "%stalloc report on '%s' "
 134                         "(total %6lu bytes in %3lu blocks)\n",
 135                         (max_depth < 0 ? "full " :""), name,
 136                         (unsigned long)talloc_total_size(ptr),
 137                         (unsigned long)talloc_total_blocks(ptr));
 138                 return;
 139         }
 140
 141         if (strcmp(name, "char") == 0) {
 142                 /*
 143                  * Print out the first 50 bytes of the string
 144                  */
 145                 state->s = talloc_asprintf_append_largebuf(
 146                         state->s, &state->str_len,
 147                         "%*s%-30s contains %6lu bytes in %3lu blocks "
 148                         "(ref %zu): %*s\n", depth*4, "", name,
 149                         (unsigned long)talloc_total_size(ptr),
 150                         (unsigned long)talloc_total_blocks(ptr),
 151                         talloc_reference_count(ptr),
 152                         (int)MIN(50, talloc_get_size(ptr)),
 153                         (const char *)ptr);
 154                 return;
 155         }
 156
 157         state->s = talloc_asprintf_append_largebuf(
 158                 state->s, &state->str_len,
 159                 "%*s%-30s contains %6lu bytes in %3lu blocks (ref %zu) %p\n",
 160                 depth*4, "", name,
 161                 (unsigned long)talloc_total_size(ptr),
 162                 (unsigned long)talloc_total_blocks(ptr),
 163                 talloc_reference_count(ptr), ptr);
 164 }
 165
 166 char *talloc_report_str(TALLOC_CTX *mem_ctx, TALLOC_CTX *root)
 167 {
 168         struct talloc_report_str_state state;
 169
 170         state.s = talloc_strdup(mem_ctx, "");
 171         if (state.s == NULL) {
 172                 return NULL;
 173         }
 174         state.str_len = 0;
 175
 176         talloc_report_depth_cb(root, 0, -1, talloc_report_str_helper, &state);
 177
 178         if (state.str_len == -1) {
 179                 talloc_free(state.s);
 180                 return NULL;
 181         }
 182
 183         return talloc_realloc(mem_ctx, state.s, char, state.str_len+1);
 184 }