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;
  37         char *start, *tmpbuf;
  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         } else {
  56                 start = NULL;
  57                 space = 0;
  58         }
  59
  60         va_copy(ap2, ap);
  61         printlen = vsnprintf(start, space, fmt, ap2);
  62         va_end(ap2);
  63
  64         if (printlen < 0) {
  65                 goto fail;
  66         }
  67
  68         needed = str_len + printlen + 1;
  69
  70         if (needed > buflen) {
  71                 buflen = MAX(128, buflen);
  72
  73                 while (buflen < needed) {
  74                         buflen *= 2;
  75                 }
  76
  77                 tmpbuf = talloc_realloc(NULL, buf, char, buflen);
  78                 if (tmpbuf == NULL) {
  79                         goto fail;
  80                 }
  81                 buf = tmpbuf;
  82
  83                 va_copy(ap2, ap);
  84                 vsnprintf(buf + str_len, buflen - str_len, fmt, ap2);
  85                 va_end(ap2);
  86         }
  87         *pstr_len = (needed - 1);
  88         return buf;
  89 fail:
  90         *pstr_len = -1;
  91         return buf;
  92 }
  93
  94 static char *talloc_asprintf_append_largebuf(char *buf, ssize_t *pstr_len,
  95                                              const char *fmt, ...)
  96                                              PRINTF_ATTRIBUTE(3,4);
  97
  98 static char *talloc_asprintf_append_largebuf(char *buf, ssize_t *pstr_len,
  99                                              const char *fmt, ...)
 100 {
 101         va_list ap;
 102
 103         va_start(ap, fmt);
 104         buf = talloc_vasprintf_append_largebuf(buf, pstr_len, fmt, ap);
 105         va_end(ap);
 106         return buf;
 107 }
 108
 109 struct talloc_report_str_state {
 110         ssize_t str_len;
 111         char *s;
 112 };
 113
 114 static void talloc_report_str_helper(const void *ptr, int depth, int max_depth,
 115                                      int is_ref, void *private_data)
 116 {
 117         struct talloc_report_str_state *state = private_data;
 118         const char *name = talloc_get_name(ptr);
 119
 120         if (ptr == state->s) {
 121                 return;
 122         }
 123
 124         if (is_ref) {
 125                 state->s = talloc_asprintf_append_largebuf(
 126                         state->s, &state->str_len,
 127                         "%*sreference to: %s\n", depth*4, "", name);
 128                 return;
 129         }
 130
 131         if (depth == 0) {
 132                 state->s = talloc_asprintf_append_largebuf(
 133                         state->s, &state->str_len,
 134                         "%stalloc report on '%s' "
 135                         "(total %6lu bytes in %3lu blocks)\n",
 136                         (max_depth < 0 ? "full " :""), name,
 137                         (unsigned long)talloc_total_size(ptr),
 138                         (unsigned long)talloc_total_blocks(ptr));
 139                 return;
 140         }
 141
 142         if (strcmp(name, "char") == 0) {
 143                 /*
 144                  * Print out the first 50 bytes of the string
 145                  */
 146                 state->s = talloc_asprintf_append_largebuf(
 147                         state->s, &state->str_len,
 148                         "%*s%-30s contains %6lu bytes in %3lu blocks "
 149                         "(ref %zu): %*s\n", depth*4, "", name,
 150                         (unsigned long)talloc_total_size(ptr),
 151                         (unsigned long)talloc_total_blocks(ptr),
 152                         talloc_reference_count(ptr),
 153                         (int)MIN(50, talloc_get_size(ptr)),
 154                         (const char *)ptr);
 155                 return;
 156         }
 157
 158         state->s = talloc_asprintf_append_largebuf(
 159                 state->s, &state->str_len,
 160                 "%*s%-30s contains %6lu bytes in %3lu blocks (ref %zu) %p\n",
 161                 depth*4, "", name,
 162                 (unsigned long)talloc_total_size(ptr),
 163                 (unsigned long)talloc_total_blocks(ptr),
 164                 talloc_reference_count(ptr), ptr);
 165 }
 166
 167 char *talloc_report_str(TALLOC_CTX *mem_ctx, TALLOC_CTX *root)
 168 {
 169         struct talloc_report_str_state state;
 170
 171         state.s = talloc_strdup(mem_ctx, "");
 172         if (state.s == NULL) {
 173                 return NULL;
 174         }
 175         state.str_len = 0;
 176
 177         talloc_report_depth_cb(root, 0, -1, talloc_report_str_helper, &state);
 178
 179         if (state.str_len == -1) {
 180                 talloc_free(state.s);
 181                 return NULL;
 182         }
 183
 184         return talloc_realloc(mem_ctx, state.s, char, state.str_len+1);
 185 }