formats/ctf/types/string.c

   1 /*
   2  * Common Trace Format
   3  *
   4  * Strings read/write functions.
   5  *
   6  * Copyright 2010 - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
   7  *
   8  * Permission is hereby granted, free of charge, to any person obtaining a copy
   9  * of this software and associated documentation files (the "Software"), to deal
  10  * in the Software without restriction, including without limitation the rights
  11  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  12  * copies of the Software, and to permit persons to whom the Software is
  13  * furnished to do so, subject to the following conditions:
  14  *
  15  * The above copyright notice and this permission notice shall be included in
  16  * all copies or substantial portions of the Software.
  17  */
  18
  19 #include <babeltrace/babeltrace.h>
  20 #include <babeltrace/ctf/types.h>
  21 #include <limits.h>             /* C99 limits */
  22 #include <string.h>
  23
  24 int ctf_string_read(struct stream_pos *ppos, struct definition *definition)
  25 {
  26         struct definition_string *string_definition =
  27                 container_of(definition, struct definition_string, p);
  28         const struct declaration_string *string_declaration =
  29                 string_definition->declaration;
  30         struct ctf_stream_pos *pos = ctf_pos(ppos);
  31         size_t len;
  32         ssize_t max_len;
  33         char *srcaddr;
  34
  35         ctf_align_pos(pos, string_declaration->p.alignment);
  36
  37         srcaddr = ctf_get_pos_addr(pos);
  38         /* Not counting \0 */
  39         max_len = pos->packet_size - pos->offset - 1;
  40         if (max_len < 0)
  41                 return -EFAULT;
  42         len = strnlen(srcaddr, max_len) + 1;    /* Add \0 */
  43         /* Truncated string, unexpected. Trace probably corrupted. */
  44         if (srcaddr[len - 1] != '\0')
  45                 return -EFAULT;
  46
  47         if (string_definition->alloc_len < len) {
  48                 string_definition->value =
  49                         g_realloc(string_definition->value, len);
  50                 string_definition->alloc_len = len;
  51         }
  52         printf_debug("CTF string read %s\n", srcaddr);
  53         memcpy(string_definition->value, srcaddr, len);
  54         string_definition->len = len;
  55         ctf_move_pos(pos, len * CHAR_BIT);
  56         return 0;
  57 }
  58
  59 int ctf_string_write(struct stream_pos *ppos,
  60                       struct definition *definition)
  61 {
  62         struct definition_string *string_definition =
  63                 container_of(definition, struct definition_string, p);
  64         const struct declaration_string *string_declaration =
  65                 string_definition->declaration;
  66         struct ctf_stream_pos *pos = ctf_pos(ppos);
  67         size_t len;
  68         char *destaddr;
  69
  70         ctf_align_pos(pos, string_declaration->p.alignment);
  71         assert(string_definition->value != NULL);
  72         len = string_definition->len;
  73
  74         if (!ctf_pos_access_ok(pos, len))
  75                 return -EFAULT;
  76
  77         if (pos->dummy)
  78                 goto end;
  79         destaddr = ctf_get_pos_addr(pos);
  80         memcpy(destaddr, string_definition->value, len);
  81 end:
  82         ctf_move_pos(pos, len * CHAR_BIT);
  83         return 0;
  84 }