formats/ctf/types/string.c

   1 /*
   2  * Common Trace Format
   3  *
   4  * Strings read/write functions.
   5  *
   6  * Copyright 2010-2011 EfficiOS Inc. and Linux Foundation
   7  *
   8  * Author: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
   9  *
  10  * Permission is hereby granted, free of charge, to any person obtaining a copy
  11  * of this software and associated documentation files (the "Software"), to deal
  12  * in the Software without restriction, including without limitation the rights
  13  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  14  * copies of the Software, and to permit persons to whom the Software is
  15  * furnished to do so, subject to the following conditions:
  16  *
  17  * The above copyright notice and this permission notice shall be included in
  18  * all copies or substantial portions of the Software.
  19  *
  20  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  21  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  22  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  23  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  24  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  25  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  26  * SOFTWARE.
  27  */
  28
  29 #include <babeltrace/babeltrace-internal.h>
  30 #include <babeltrace/ctf/types.h>
  31 #include <limits.h>             /* C99 limits */
  32 #include <babeltrace/compat/string.h>
  33
  34 int ctf_string_read(struct bt_stream_pos *ppos, struct bt_definition *definition)
  35 {
  36         struct definition_string *string_definition =
  37                 container_of(definition, struct definition_string, p);
  38         const struct declaration_string *string_declaration =
  39                 string_definition->declaration;
  40         struct ctf_stream_pos *pos = ctf_pos(ppos);
  41         size_t len;
  42         ssize_t max_len_bits;
  43         char *srcaddr;
  44
  45         if (!ctf_align_pos(pos, string_declaration->p.alignment))
  46                 return -EFAULT;
  47
  48         srcaddr = ctf_get_pos_addr(pos);
  49         if (pos->offset == EOF)
  50                 return -EFAULT;
  51         /* Not counting \0. Counting in bits. */
  52         max_len_bits = pos->packet_size - pos->offset - CHAR_BIT;
  53         if (max_len_bits < 0)
  54                 return -EFAULT;
  55         /* Add \0, counting in bytes. */
  56         len = bt_strnlen(srcaddr, (size_t) max_len_bits / CHAR_BIT) + 1;
  57         /* Truncated string, unexpected. Trace probably corrupted. */
  58         if (srcaddr[len - 1] != '\0')
  59                 return -EFAULT;
  60
  61         if (string_definition->alloc_len < len) {
  62                 string_definition->value =
  63                         g_realloc(string_definition->value, len);
  64                 string_definition->alloc_len = len;
  65         }
  66         printf_debug("CTF string read %s\n", srcaddr);
  67         memcpy(string_definition->value, srcaddr, len);
  68         string_definition->len = len;
  69         if (!ctf_move_pos(pos, len * CHAR_BIT))
  70                 return -EFAULT;
  71         return 0;
  72 }
  73
  74 int ctf_string_write(struct bt_stream_pos *ppos,
  75                       struct bt_definition *definition)
  76 {
  77         struct definition_string *string_definition =
  78                 container_of(definition, struct definition_string, p);
  79         const struct declaration_string *string_declaration =
  80                 string_definition->declaration;
  81         struct ctf_stream_pos *pos = ctf_pos(ppos);
  82         size_t len;
  83         char *destaddr;
  84
  85         if (!ctf_align_pos(pos, string_declaration->p.alignment))
  86                 return -EFAULT;
  87         assert(string_definition->value != NULL);
  88         len = string_definition->len;
  89
  90         if (!ctf_pos_access_ok(pos, len))
  91                 return -EFAULT;
  92
  93         if (pos->dummy)
  94                 goto end;
  95         destaddr = ctf_get_pos_addr(pos);
  96         memcpy(destaddr, string_definition->value, len);
  97 end:
  98         if (!ctf_move_pos(pos, len * CHAR_BIT))
  99                 return -EFAULT;
 100         return 0;
 101 }