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
  21 #include <babeltrace/babeltrace-internal.h>
  22 #include <babeltrace/ctf/types.h>
  23 #include <limits.h>             /* C99 limits */
  24 #include <string.h>
  25
  26 int ctf_string_read(struct stream_pos *ppos, struct definition *definition)
  27 {
  28         struct definition_string *string_definition =
  29                 container_of(definition, struct definition_string, p);
  30         const struct declaration_string *string_declaration =
  31                 string_definition->declaration;
  32         struct ctf_stream_pos *pos = ctf_pos(ppos);
  33         size_t len;
  34         ssize_t max_len;
  35         char *srcaddr;
  36
  37         ctf_align_pos(pos, string_declaration->p.alignment);
  38
  39         srcaddr = ctf_get_pos_addr(pos);
  40         if (pos->offset == EOF)
  41                 return -EFAULT;
  42         /* Not counting \0 */
  43         max_len = pos->packet_size - pos->offset - 1;
  44         if (max_len < 0)
  45                 return -EFAULT;
  46         len = strnlen(srcaddr, max_len) + 1;    /* Add \0 */
  47         /* Truncated string, unexpected. Trace probably corrupted. */
  48         if (srcaddr[len - 1] != '\0')
  49                 return -EFAULT;
  50
  51         if (string_definition->alloc_len < len) {
  52                 string_definition->value =
  53                         g_realloc(string_definition->value, len);
  54                 string_definition->alloc_len = len;
  55         }
  56         printf_debug("CTF string read %s\n", srcaddr);
  57         memcpy(string_definition->value, srcaddr, len);
  58         string_definition->len = len;
  59         ctf_move_pos(pos, len * CHAR_BIT);
  60         return 0;
  61 }
  62
  63 int ctf_string_write(struct stream_pos *ppos,
  64                       struct definition *definition)
  65 {
  66         struct definition_string *string_definition =
  67                 container_of(definition, struct definition_string, p);
  68         const struct declaration_string *string_declaration =
  69                 string_definition->declaration;
  70         struct ctf_stream_pos *pos = ctf_pos(ppos);
  71         size_t len;
  72         char *destaddr;
  73
  74         ctf_align_pos(pos, string_declaration->p.alignment);
  75         assert(string_definition->value != NULL);
  76         len = string_definition->len;
  77
  78         if (!ctf_pos_access_ok(pos, len))
  79                 return -EFAULT;
  80
  81         if (pos->dummy)
  82                 goto end;
  83         destaddr = ctf_get_pos_addr(pos);
  84         memcpy(destaddr, string_definition->value, len);
  85 end:
  86         ctf_move_pos(pos, len * CHAR_BIT);
  87         return 0;
  88 }