/*
* Error handling for libcdecl.
- * Copyright © 2011-2012, 2021 Nick Bowler
+ * Copyright © 2011-2012, 2021, 2023 Nick Bowler
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
#include <assert.h>
#include <stdarg.h>
+#include "cdecl.h"
+#include "cdecl-internal.h"
+
#include <glthread/lock.h>
#include <glthread/tls.h>
-#include "cdecl.h"
-#include "cdecl-internal.h"
+#include "errmsg.h"
-gl_once_define(static, tls_initialized);
+gl_once_define(static, tls_initialized)
static gl_tls_key_t tls_key;
struct err_state {
char str[FLEXIBLE_ARRAY_MEMBER];
};
-/* This error is reserved for extremely dire out-of-memory conditions. */
-static struct err_state err_no_mem = {
- .err = {
- .code = CDECL_ENOMEM,
- .str = NULL,
- },
-};
+/* This pre-initialized error is reserved for dire out-of-memory conditions. */
+static struct cdecl_error err_no_mem;
static void free_err(void *err)
{
free(err);
}
+static void set_err(unsigned code, struct cdecl_error *err)
+{
+ static const char errmsgs[] = STRTAB_INITIALIZER;
+
+ switch (code) {
+ case CDECL__ENOMEM:
+ err->code = CDECL_ENOMEM;
+ break;
+ default:
+ err->code = CDECL_ENOPARSE;
+ break;
+ }
+
+ err->str = _(&errmsgs[code]);
+}
+
static void initialize(void)
{
cdecl__init_i18n();
- err_no_mem.err.str = _("failed to allocate memory");
-
+ set_err(CDECL__ENOMEM, &err_no_mem);
gl_tls_key_init(tls_key, free_err);
}
-/*
- * cdecl__err(CDECL_ENOMEM);
- * cdecl__err(code, fmt, ...);
- *
- * Sets the library error to code, with a printf-style error string.
- */
-void cdecl__err(unsigned code, ...)
+static void *alloc_err_state(void *old, size_t buf_size)
{
- const char *fmt;
struct err_state *state;
- int rc, try = 0;
- va_list ap;
+ void *p;
+
+ state = p = realloc(old, offsetof(struct err_state, str) + buf_size);
+ if (state) {
+ state->nstr = buf_size;
+ } else if (old) {
+ /* Failed allocation, but existing state is still good */
+ p = old;
+ } else {
+ /* Failed allocation, no existing state */
+ p = &err_no_mem;
+ }
+
+ gl_tls_set(tls_key, p);
+ return state;
+}
+
+static struct err_state *get_err_state(void)
+{
+ void *state;
gl_once(tls_initialized, initialize);
state = gl_tls_get(tls_key);
- if (!state || state == &err_no_mem) {
- void *tmp = malloc(sizeof *state + 100);
+ if (state == &err_no_mem)
+ state = NULL;
+ if (!state)
+ return alloc_err_state(state, 100);
+ return state;
+}
- if (!tmp) {
- state = &err_no_mem;
- return;
- }
+/*
+ * Set the library error to one of the preset messages defined in errmsg.h
+ * (CDECL__Exxx).
+ */
+void cdecl__errmsg(unsigned msg)
+{
+ struct err_state *state;
- gl_tls_set(tls_key, (state = tmp));
- state->nstr = 100;
- }
+ state = get_err_state();
+ if (!state)
+ return;
+
+ set_err(msg, &state->err);
+}
+
+/*
+ * Sets the library error to code, with a printf-style error string.
+ */
+void cdecl__err(unsigned code, const char *fmt, ...)
+{
+ struct err_state *state;
+ int rc, try = 0;
+ va_list ap;
- if (code == CDECL_ENOMEM) {
- if (state != &err_no_mem)
- state->err = err_no_mem.err;
+ state = get_err_state();
+ if (!state)
return;
- }
+
retry:
- va_start(ap, code);
- fmt = va_arg(ap, const char *);
+ va_start(ap, fmt);
rc = vsnprintf(state->str, state->nstr, fmt, ap);
va_end(ap);
if (rc > 0 && rc >= state->nstr) {
- void *tmp;
- size_t n;
-
- assert(try == 0 && rc < SIZE_MAX / 4);
-
- n = ((size_t)rc + 1) * 2;
- tmp = realloc(state, sizeof *state + n);
- if (tmp) {
- state = tmp;
- state->nstr = n;
- try++;
-
- goto retry;
- }
+ assert(try++ == 0 && rc < SIZE_MAX / 4);
+ state = alloc_err_state(state, (size_t)(rc+1u) * 3 / 2);
+ if (!state)
+ return;
- state->err = err_no_mem.err;
- return;
+ goto retry;
}
state->err.str = state->str;
const struct cdecl_error *cdecl_get_error(void)
{
- struct err_state *state;
+ struct err_state *state = get_err_state();
- gl_once(tls_initialized, initialize);
-
- state = gl_tls_get(tls_key);
return state ? &state->err : NULL;
}