/*
- * Copyright (c) 2008, 2009, 2010 Nicira Networks.
+ * Copyright (c) 2008, 2009, 2010, 2011 Nicira Networks.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
#include <config.h>
#include "util.h"
+#include <assert.h>
#include <errno.h>
+#include <limits.h>
#include <stdarg.h>
+#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
COVERAGE_DEFINE(util_xalloc);
const char *program_name;
+static char *program_version;
void
out_of_memory(void)
{
- ovs_fatal(0, "virtual memory exhausted");
+ ovs_abort(0, "virtual memory exhausted");
}
void *
return s;
}
+/* Similar to strlcpy() from OpenBSD, but it never reads more than 'size - 1'
+ * bytes from 'src' and doesn't return anything. */
void
ovs_strlcpy(char *dst, const char *src, size_t size)
{
if (size > 0) {
- size_t n = strlen(src);
- size_t n_copy = MIN(n, size - 1);
- memcpy(dst, src, n_copy);
- dst[n_copy] = '\0';
+ size_t len = strnlen(src, size - 1);
+ memcpy(dst, src, len);
+ dst[len] = '\0';
}
}
+/* Copies 'src' to 'dst'. Reads no more than 'size - 1' bytes from 'src'.
+ * Always null-terminates 'dst' (if 'size' is nonzero), and writes a zero byte
+ * to every otherwise unused byte in 'dst'.
+ *
+ * Except for performance, the following call:
+ * ovs_strzcpy(dst, src, size);
+ * is equivalent to these two calls:
+ * memset(dst, '\0', size);
+ * ovs_strlcpy(dst, src, size);
+ *
+ * (Thus, ovs_strzcpy() is similar to strncpy() without some of the pitfalls.)
+ */
void
-ovs_fatal(int err_no, const char *format, ...)
+ovs_strzcpy(char *dst, const char *src, size_t size)
+{
+ if (size > 0) {
+ size_t len = strnlen(src, size - 1);
+ memcpy(dst, src, len);
+ memset(dst + len, '\0', size - len);
+ }
+}
+
+/* Prints 'format' on stderr, formatting it like printf() does. If 'err_no' is
+ * nonzero, then it is formatted with ovs_retval_to_string() and appended to
+ * the message inside parentheses. Then, terminates with abort().
+ *
+ * This function is preferred to ovs_fatal() in a situation where it would make
+ * sense for a monitoring process to restart the daemon.
+ *
+ * 'format' should not end with a new-line, because this function will add one
+ * itself. */
+void
+ovs_abort(int err_no, const char *format, ...)
{
va_list args;
- fprintf(stderr, "%s: ", program_name);
va_start(args, format);
- vfprintf(stderr, format, args);
+ ovs_error_valist(err_no, format, args);
va_end(args);
- if (err_no != 0)
- fprintf(stderr, " (%s)",
- err_no == EOF ? "end of file" : strerror(err_no));
- putc('\n', stderr);
+ abort();
+}
+
+/* Prints 'format' on stderr, formatting it like printf() does. If 'err_no' is
+ * nonzero, then it is formatted with ovs_retval_to_string() and appended to
+ * the message inside parentheses. Then, terminates with EXIT_FAILURE.
+ *
+ * 'format' should not end with a new-line, because this function will add one
+ * itself. */
+void
+ovs_fatal(int err_no, const char *format, ...)
+{
+ va_list args;
+
+ va_start(args, format);
+ ovs_fatal_valist(err_no, format, args);
+}
+
+/* Same as ovs_fatal() except that the arguments are supplied as a va_list. */
+void
+ovs_fatal_valist(int err_no, const char *format, va_list args)
+{
+ ovs_error_valist(err_no, format, args);
exit(EXIT_FAILURE);
}
+/* Prints 'format' on stderr, formatting it like printf() does. If 'err_no' is
+ * nonzero, then it is formatted with ovs_retval_to_string() and appended to
+ * the message inside parentheses.
+ *
+ * 'format' should not end with a new-line, because this function will add one
+ * itself. */
void
ovs_error(int err_no, const char *format, ...)
{
- int save_errno = errno;
va_list args;
- fprintf(stderr, "%s: ", program_name);
va_start(args, format);
- vfprintf(stderr, format, args);
+ ovs_error_valist(err_no, format, args);
va_end(args);
+}
+
+/* Same as ovs_error() except that the arguments are supplied as a va_list. */
+void
+ovs_error_valist(int err_no, const char *format, va_list args)
+{
+ int save_errno = errno;
+
+ fprintf(stderr, "%s: ", program_name);
+ vfprintf(stderr, format, args);
if (err_no != 0) {
- fprintf(stderr, " (%s)",
- err_no == EOF ? "end of file" : strerror(err_no));
+ fprintf(stderr, " (%s)", ovs_retval_to_string(err_no));
}
putc('\n', stderr);
errno = save_errno;
}
-/* Sets program_name based on 'argv0'. Should be called at the beginning of
- * main(), as "set_program_name(argv[0]);". */
-void set_program_name(const char *argv0)
+/* Many OVS functions return an int which is one of:
+ * - 0: no error yet
+ * - >0: errno value
+ * - EOF: end of file (not necessarily an error; depends on the function called)
+ *
+ * Returns the appropriate human-readable string. The caller must copy the
+ * string if it wants to hold onto it, as the storage may be overwritten on
+ * subsequent function calls.
+ */
+const char *
+ovs_retval_to_string(int retval)
+{
+ static char unknown[48];
+
+ if (!retval) {
+ return "";
+ }
+ if (retval > 0) {
+ return strerror(retval);
+ }
+ if (retval == EOF) {
+ return "End of file";
+ }
+ snprintf(unknown, sizeof unknown, "***unknown return value: %d***", retval);
+ return unknown;
+}
+
+/* Sets global "program_name" and "program_version" variables. Should
+ * be called at the beginning of main() with "argv[0]" as the argument
+ * to 'argv0'.
+ *
+ * The 'date' and 'time' arguments should likely be called with
+ * "__DATE__" and "__TIME__" to use the time the binary was built.
+ * Alternatively, the "set_program_name" macro may be called to do this
+ * automatically.
+ */
+void
+set_program_name__(const char *argv0, const char *date, const char *time)
{
const char *slash = strrchr(argv0, '/');
program_name = slash ? slash + 1 : argv0;
+
+ free(program_version);
+ program_version = xasprintf("%s (Open vSwitch) "VERSION BUILDNR"\n"
+ "Compiled %s %s\n",
+ program_name, date, time);
+}
+
+/* Returns a pointer to a string describing the program version. The
+ * caller must not modify or free the returned string.
+ */
+const char *
+get_program_version(void)
+{
+ return program_version;
}
/* Print the version information for the program. */
void
-ovs_print_version(char *date, char *time,
- uint8_t min_ofp, uint8_t max_ofp)
+ovs_print_version(uint8_t min_ofp, uint8_t max_ofp)
{
- printf("%s (Open vSwitch) "VERSION BUILDNR"\n", program_name);
- printf("Compiled %s %s\n", date, time);
+ printf("%s", program_version);
if (min_ofp || max_ofp) {
printf("OpenFlow versions %#x:%#x\n", min_ofp, max_ofp);
}
* its return value. (Note that every scalar type can be implicitly
* converted to bool.) */
void ignore(bool x OVS_UNUSED) { }
+
+/* Returns an appropriate delimiter for inserting just before the 0-based item
+ * 'index' in a list that has 'total' items in it. */
+const char *
+english_list_delimiter(size_t index, size_t total)
+{
+ return (index == 0 ? ""
+ : index < total - 1 ? ", "
+ : total > 2 ? ", and "
+ : " and ");
+}
+
+/* Given a 32 bit word 'n', calculates floor(log_2('n')). This is equivalent
+ * to finding the bit position of the most significant one bit in 'n'. It is
+ * an error to call this function with 'n' == 0. */
+int
+log_2_floor(uint32_t n)
+{
+ assert(n);
+
+#if !defined(UINT_MAX) || !defined(UINT32_MAX)
+#error "Someone screwed up the #includes."
+#elif __GNUC__ >= 4 && UINT_MAX == UINT32_MAX
+ return 31 - __builtin_clz(n);
+#else
+ {
+ int log = 0;
+
+#define BIN_SEARCH_STEP(BITS) \
+ if (n >= (1 << BITS)) { \
+ log += BITS; \
+ n >>= BITS; \
+ }
+ BIN_SEARCH_STEP(16);
+ BIN_SEARCH_STEP(8);
+ BIN_SEARCH_STEP(4);
+ BIN_SEARCH_STEP(2);
+ BIN_SEARCH_STEP(1);
+#undef BIN_SEARCH_STEP
+ return log;
+ }
+#endif
+}
git://git.onelab.eu / sliver-openvswitch.git / blobdiff