--- /dev/null
+/*
+ * Copyright (c) 2015-16 David Lamparter, for NetDEF, Inc.
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include <stdlib.h>
+#include <stdarg.h>
+#include <string.h>
+#include <pthread.h>
+#include <signal.h>
+
+#include "ferr.h"
+#include "vty.h"
+#include "jhash.h"
+#include "memory.h"
+
+DEFINE_MTYPE_STATIC(LIB, ERRINFO, "error information")
+
+static pthread_key_t errkey;
+
+static void ferr_free(void *arg)
+{
+ XFREE(MTYPE_ERRINFO, arg);
+}
+
+static void err_key_init(void) __attribute__((_CONSTRUCTOR(500)));
+static void err_key_init(void)
+{
+ pthread_key_create(&errkey, ferr_free);
+}
+
+static void err_key_fini(void) __attribute__((_DESTRUCTOR(500)));
+static void err_key_fini(void)
+{
+ pthread_key_delete(errkey);
+}
+
+const struct ferr *ferr_get_last(ferr_r errval)
+{
+ struct ferr *last_error = pthread_getspecific(errkey);
+ if (!last_error || last_error->kind == 0)
+ return NULL;
+ return last_error;
+}
+
+ferr_r ferr_clear(void)
+{
+ struct ferr *last_error = pthread_getspecific(errkey);
+ if (last_error)
+ last_error->kind = 0;
+ return ferr_ok();
+}
+
+static ferr_r ferr_set_va(const char *file, int line, const char *func,
+ enum ferr_kind kind, const char *pathname, int errno_val,
+ const char *text, va_list va)
+{
+ struct ferr *error = pthread_getspecific(errkey);
+
+ if (!error) {
+ error = XCALLOC(MTYPE_ERRINFO, sizeof(*error));
+ if (!error) {
+ /* we're screwed */
+ zlog_err("out of memory while allocating error info");
+ raise(SIGSEGV);
+ }
+
+ pthread_setspecific(errkey, error);
+ }
+
+ error->file = file;
+ error->line = line;
+ error->func = func;
+ error->kind = kind;
+
+ error->unique_id = jhash(text, strlen(text),
+ jhash(file, strlen(file), 0xd4ed0298));
+
+ error->errno_val = errno_val;
+ if (pathname)
+ snprintf(error->pathname, sizeof(error->pathname),
+ "%s", pathname);
+ else
+ error->pathname[0] = '\0';
+
+ vsnprintf(error->message, sizeof(error->message), text, va);
+ return -1;
+}
+
+ferr_r ferr_set_internal(const char *file, int line, const char *func,
+ enum ferr_kind kind, const char *text, ...)
+{
+ ferr_r rv;
+ va_list va;
+ va_start(va, text);
+ rv = ferr_set_va(file, line, func, kind, NULL, 0, text, va);
+ va_end(va);
+ return rv;
+}
+
+ferr_r ferr_set_internal_ext(const char *file, int line, const char *func,
+ enum ferr_kind kind, const char *pathname, int errno_val,
+ const char *text, ...)
+{
+ ferr_r rv;
+ va_list va;
+ va_start(va, text);
+ rv = ferr_set_va(file, line, func, kind, pathname, errno_val, text, va);
+ va_end(va);
+ return rv;
+}
+
+#define REPLACE "$ERR"
+void vty_print_error(struct vty *vty, ferr_r err, const char *msg, ...)
+{
+ char tmpmsg[512], *replacepos;
+ const struct ferr *last_error = ferr_get_last(err);
+
+ va_list va;
+ va_start(va, msg);
+ vsnprintf(tmpmsg, sizeof(tmpmsg), msg, va);
+ va_end(va);
+
+ replacepos = strstr(tmpmsg, REPLACE);
+ if (!replacepos)
+ vty_out(vty, "%s\n", tmpmsg);
+ else {
+ replacepos[0] = '\0';
+ replacepos += sizeof(REPLACE) - 1;
+ vty_out(vty, "%s%s%s\n",
+ tmpmsg,
+ last_error ? last_error->message : "(no error?)",
+ replacepos);
+ }
+}
+
--- /dev/null
+/*
+ * Copyright (c) 2015-16 David Lamparter, for NetDEF, Inc.
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#ifndef _FRR_FERR_H
+#define _FRR_FERR_H
+
+/***********************************************************
+ * scroll down to the end of this file for a full example! *
+ ***********************************************************/
+
+#include <stdint.h>
+#include <limits.h>
+#include <errno.h>
+
+/* return type when this error indication stuff is used.
+ *
+ * guaranteed to have boolean evaluation to "false" when OK, "true" when error
+ * (i.e. can be changed to pointer in the future if neccessary)
+ *
+ * For checking, always use "if (value)", nothing else.
+ * Do _NOT_ use any integer constant (!= 0), or sign check (< 0).
+ */
+typedef int ferr_r;
+
+/* rough category of error indication */
+enum ferr_kind {
+ /* no error */
+ FERR_OK = 0,
+
+ /* something isn't the way it's supposed to be.
+ * (things that might otherwise be asserts, really)
+ */
+ FERR_CODE_BUG,
+
+ /* user-supplied parameters don't make sense or is inconsistent
+ * if you can express a rule for it (e.g. "holdtime > 2 * keepalive"),
+ * it's this category.
+ */
+ FERR_CONFIG_INVALID,
+
+ /* user-supplied parameters don't line up with reality
+ * (IP address or interface not available, etc.)
+ * NB: these are really TODOs where the code needs to be fixed to
+ * respond to future changes!
+ */
+ FERR_CONFIG_REALITY,
+
+ /* out of some system resource (probably memory)
+ * aka "you didn't spend enough money error" */
+ FERR_RESOURCE,
+
+ /* system error (permission denied, etc.) */
+ FERR_SYSTEM,
+
+ /* error return from some external library
+ * (FERR_SYSTEM and FERR_LIBRARY are not strongly distinct) */
+ FERR_LIBRARY,
+};
+
+struct ferr {
+ /* code location */
+ const char *file;
+ const char *func;
+ int line;
+
+ enum ferr_kind kind;
+
+ /* unique_id is calculated as a checksum of source filename and error
+ * message format (*before* calling vsnprintf). Line number and
+ * function name are not used; this keeps the number reasonably static
+ * across changes.
+ */
+ uint32_t unique_id;
+
+ char message[384];
+
+ /* valid if != 0. note "errno" might be preprocessor foobar. */
+ int errno_val;
+ /* valid if pathname[0] != '\0' */
+ char pathname[PATH_MAX];
+};
+
+/* get error details.
+ *
+ * NB: errval/ferr_r does NOT carry the full error information. It's only
+ * passed around for future API flexibility. ferr_get_last always returns
+ * the last error set in the current thread.
+ */
+const struct ferr *ferr_get_last(ferr_r errval);
+
+/* can optionally be called at strategic locations.
+ * always returns 0. */
+ferr_r ferr_clear(void);
+
+/* do NOT call these functions directly. only for macro use! */
+ferr_r ferr_set_internal(const char *file, int line, const char *func,
+ enum ferr_kind kind, const char *text, ...);
+ferr_r ferr_set_internal_ext(const char *file, int line, const char *func,
+ enum ferr_kind kind, const char *pathname, int errno_val,
+ const char *text, ...);
+
+#define ferr_ok() \
+ 0
+
+/* Report an error.
+ *
+ * If you need to do cleanup (free memory, etc.), save the return value in a
+ * variable of type ferr_r.
+ *
+ * Don't put a \n at the end of the error message.
+ */
+#define ferr_code_bug(...) \
+ ferr_set_internal(__FILE__, __LINE__, __func__, FERR_CODE_BUG, \
+ __VA_ARGS__)
+#define ferr_cfg_invalid(...) \
+ ferr_set_internal(__FILE__, __LINE__, __func__, FERR_CONFIG_INVALID, \
+ __VA_ARGS__)
+#define ferr_cfg_reality(...) \
+ ferr_set_internal(__FILE__, __LINE__, __func__, FERR_CONFIG_REALITY, \
+ __VA_ARGS__)
+#define ferr_cfg_resource(...) \
+ ferr_set_internal(__FILE__, __LINE__, __func__, FERR_RESOURCE, \
+ __VA_ARGS__)
+#define ferr_system(...) \
+ ferr_set_internal(__FILE__, __LINE__, __func__, FERR_SYSTEM, \
+ __VA_ARGS__)
+#define ferr_library(...) \
+ ferr_set_internal(__FILE__, __LINE__, __func__, FERR_LIBRARY, \
+ __VA_ARGS__)
+
+/* extended information variants */
+#define ferr_system_errno(...) \
+ ferr_set_internal_ext(__FILE__, __LINE__, __func__, FERR_SYSTEM, \
+ NULL, errno, __VA_ARGS__)
+#define ferr_system_path_errno(path, ...) \
+ ferr_set_internal_ext(__FILE__, __LINE__, __func__, FERR_SYSTEM, \
+ path, errno, __VA_ARGS__)
+
+#include "vty.h"
+/* print error message to vty; $ERR is replaced by the error's message */
+void vty_print_error(struct vty *vty, ferr_r err, const char *msg, ...);
+
+#define CMD_FERR_DO(func, action, ...) \
+ do { ferr_r cmd_retval = func; \
+ if (cmd_retval) { \
+ vty_print_error(vty, cmd_retval, __VA_ARGS__); \
+ action; \
+ } \
+ } while (0)
+
+#define CMD_FERR_RETURN(func, ...) \
+ CMD_FERR_DO(func, return CMD_WARNING, __VA_ARGS__)
+#define CMD_FERR_GOTO(func, label, ...) \
+ CMD_FERR_DO(func, goto label, __VA_ARGS__)
+
+/* example:
+
+ferr_r foo_bar_set(struct object *obj, int bar)
+{
+ if (bar < 1 || bar >= 100)
+ return ferr_config_invalid("bar setting (%d) must be 0<x<100", bar);
+ obj->bar = bar;
+ if (ioctl (obj->fd, bar))
+ return ferr_system_errno("couldn't set bar to %d", bar);
+
+ return ferr_ok();
+}
+
+DEFUN("bla")
+{
+ CMD_FERR_RETURN(foo_bar_set(obj, atoi(argv[1])),
+ "command failed: $ERR\n");
+ return CMD_SUCCESS;
+}
+
+*/
+
+#endif /* _FERR_H */
projects / mirror / frr.git / commitdiff