2 * Error handling for libcdecl.
3 * Copyright © 2011-2012, 2021, 2023 Nick Bowler
5 * This program is free software: you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation, either version 3 of the License, or
8 * (at your option) any later version.
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
15 * You should have received a copy of the GNU General Public License
16 * along with this program. If not, see <http://www.gnu.org/licenses/>.
27 #include "cdecl-internal.h"
29 #include <glthread/lock.h>
30 #include <glthread/tls.h>
32 gl_once_define(static, tls_initialized);
33 static gl_tls_key_t tls_key;
36 struct cdecl_error err;
38 char str[FLEXIBLE_ARRAY_MEMBER];
41 /* This pre-initialized error is reserved for dire out-of-memory conditions. */
42 static struct cdecl_error err_no_mem;
44 static void free_err(void *err)
46 if (err == &err_no_mem)
52 static void initialize(void)
55 err_no_mem.str = _("failed to allocate memory");
56 gl_tls_key_init(tls_key, free_err);
59 static void *alloc_err_state(void *old, size_t buf_size)
61 struct err_state *state;
64 state = p = realloc(old, offsetof(struct err_state, str) + buf_size);
66 state->nstr = buf_size;
68 /* Failed allocation, but existing state is still good */
71 /* Failed allocation, no existing state */
75 gl_tls_set(tls_key, p);
79 static struct err_state *get_err_state(void)
83 gl_once(tls_initialized, initialize);
85 state = gl_tls_get(tls_key);
86 if (state == &err_no_mem)
89 return alloc_err_state(state, 100);
94 * cdecl__err(CDECL_ENOMEM);
95 * cdecl__err(code, fmt, ...);
97 * Sets the library error to code, with a printf-style error string.
99 void cdecl__err(unsigned code, ...)
102 struct err_state *state;
106 state = get_err_state();
110 if (code == CDECL_ENOMEM) {
111 state->err.code = code;
112 state->err.str = err_no_mem.str;
117 fmt = va_arg(ap, const char *);
118 rc = vsnprintf(state->str, state->nstr, fmt, ap);
121 if (rc > 0 && rc >= state->nstr) {
122 assert(try++ == 0 && rc < SIZE_MAX / 4);
123 state = alloc_err_state(state, (size_t)(rc+1u) * 3 / 2);
130 state->err.str = state->str;
131 state->err.code = code;
134 const struct cdecl_error *cdecl_get_error(void)
136 struct err_state *state = get_err_state();
138 return state ? &state->err : NULL;