src/error.c

   1 #include <config.h>
   2 #include <stdlib.h>
   3 #include <string.h>
   4 #include <assert.h>
   5 #include <glthread/lock.h>
   6 #include <glthread/tls.h>
   7 #include "cdecl.h"
   8 #include "error.h"
   9 #include "i18n.h"
  10
  11 gl_once_define(static, tls_initialized);
  12 static gl_tls_key_t tls_key;
  13
  14 struct err_state {
  15         struct cdecl_error err;
  16         size_t nstr;
  17         char str[];
  18 };
  19
  20 /* This error is reserved for extremely dire out-of-memory conditions. */
  21 static struct err_state err_no_mem = {
  22         .err = {
  23                 .code = CDECL_ENOMEM,
  24                 .str  = "failed to allocate memory",
  25         },
  26 };
  27
  28 static void free_err(void *err)
  29 {
  30         if (err == &err_no_mem)
  31                 return;
  32
  33         free(err);
  34 }
  35
  36 static void initialize(void)
  37 {
  38         cdecl__init_i18n();
  39         err_no_mem.err.str = gettext(err_no_mem.err.str);
  40
  41         gl_tls_key_init(tls_key, free_err);
  42
  43         /*
  44          * This default error message is a stop-gap measure until all library
  45          * error conditions use the new interface.
  46          */
  47         cdecl__set_error(&(const struct cdecl_error){ .code = CDECL_ENOPARSE });
  48 }
  49
  50 const struct cdecl_error *cdecl_get_error(void)
  51 {
  52         struct err_state *state;
  53
  54         gl_once(tls_initialized, initialize);
  55
  56         state = gl_tls_get(tls_key);
  57         assert(state);
  58
  59         return &state->err;
  60 }
  61
  62 void cdecl__set_error(const struct cdecl_error *err)
  63 {
  64         struct err_state *state;
  65         size_t need_len = 0;
  66
  67         gl_once(tls_initialized, initialize);
  68
  69         if (err->str) {
  70                 need_len = strlen(err->str) + 1;
  71         }
  72
  73         state = gl_tls_get(tls_key);
  74         if (state == &err_no_mem)
  75                 state = NULL;
  76         if (!state || state->nstr < need_len) {
  77                 struct err_state *tmp;
  78
  79                 tmp = realloc(state, sizeof *state + need_len);
  80                 if (!tmp) {
  81                         /* Re-use the existing state buffer, if any. */
  82                         if (state)
  83                                 state->err = err_no_mem.err;
  84                         else
  85                                 state = &err_no_mem;
  86
  87                         gl_tls_set(tls_key, state);
  88                         return;
  89                 }
  90
  91                 state = tmp;
  92                 state->nstr = need_len;
  93                 gl_tls_set(tls_key, state);
  94         }
  95
  96         state->err = *err;
  97         if (err->str) {
  98                 memcpy(state->str, err->str, need_len);
  99                 state->err.str = state->str;
 100         } else {
 101                 state->err.str = "unknown error";
 102         }
 103 }