X-Git-Url: https://pintos-os.org/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=lib%2Futil.c;h=1a42376e21216fc0c3a07ea928dd172719f1515e;hb=2c6d841118a6b14cc5b03fc3b549143a6b7ce143;hp=19f13dddc1f3f902b9964354e49381cd2221b8ef;hpb=daf03c53ee14a0227b43330be2e638b9ad9ce022;p=openvswitch

diff --git a/lib/util.c b/lib/util.c
index 19f13ddd..1a42376e 100644
--- a/lib/util.c
+++ b/lib/util.c
@@ -1,5 +1,5 @@
 /*
- * 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.
@@ -23,20 +23,22 @@
 #include <string.h>
 #include <unistd.h>
 #include "coverage.h"
-
-#define THIS_MODULE VLM_util
 #include "vlog.h"
 
+VLOG_DEFINE_THIS_MODULE(util);
+
+COVERAGE_DEFINE(util_xalloc);
+
 const char *program_name;
 
 void
-out_of_memory(void) 
+out_of_memory(void)
 {
-    ovs_fatal(0, "virtual memory exhausted");
+    ovs_abort(0, "virtual memory exhausted");
 }
 
 void *
-xcalloc(size_t count, size_t size) 
+xcalloc(size_t count, size_t size)
 {
     void *p = count && size ? calloc(count, size) : malloc(1);
     COVERAGE_INC(util_xalloc);
@@ -53,7 +55,7 @@ xzalloc(size_t size)
 }
 
 void *
-xmalloc(size_t size) 
+xmalloc(size_t size)
 {
     void *p = malloc(size ? size : 1);
     COVERAGE_INC(util_xalloc);
@@ -64,7 +66,7 @@ xmalloc(size_t size)
 }
 
 void *
-xrealloc(void *p, size_t size) 
+xrealloc(void *p, size_t size)
 {
     p = realloc(p, size ? size : 1);
     COVERAGE_INC(util_xalloc);
@@ -92,7 +94,7 @@ xmemdup0(const char *p_, size_t length)
 }
 
 char *
-xstrdup(const char *s) 
+xstrdup(const char *s)
 {
     return xmemdup0(s, strlen(s));
 }
@@ -135,52 +137,143 @@ xasprintf(const char *format, ...)
     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)", 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;
 }
 
+/* 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 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)
@@ -191,7 +284,7 @@ void set_program_name(const char *argv0)
 
 /* Print the version information for the program.  */
 void
-ovs_print_version(char *date, char *time, 
+ovs_print_version(char *date, char *time,
                   uint8_t min_ofp, uint8_t max_ofp)
 {
     printf("%s (Open vSwitch) "VERSION BUILDNR"\n", program_name);
@@ -357,9 +450,37 @@ hexit_value(int c)
 
     case 'f': case 'F':
         return 0xf;
+
+    default:
+        return -1;
     }
+}
 
-    NOT_REACHED();
+/* Returns the integer value of the 'n' hexadecimal digits starting at 's', or
+ * UINT_MAX if one of those "digits" is not really a hex digit.  If 'ok' is
+ * nonnull, '*ok' is set to true if the conversion succeeds or to false if a
+ * non-hex digit is detected. */
+unsigned int
+hexits_value(const char *s, size_t n, bool *ok)
+{
+    unsigned int value;
+    size_t i;
+
+    value = 0;
+    for (i = 0; i < n; i++) {
+        int hexit = hexit_value(s[i]);
+        if (hexit < 0) {
+            if (ok) {
+                *ok = false;
+            }
+            return UINT_MAX;
+        }
+        value = (value << 4) + hexit;
+    }
+    if (ok) {
+        *ok = true;
+    }
+    return value;
 }
 
 /* Returns the current working directory as a malloc()'d string, or a null
@@ -393,6 +514,14 @@ get_cwd(void)
     }
 }
 
+static char *
+all_slashes_name(const char *s)
+{
+    return xstrdup(s[0] == '/' && s[1] == '/' && s[2] != '/' ? "//"
+                   : s[0] == '/' ? "/"
+                   : ".");
+}
+
 /* Returns the directory name portion of 'file_name' as a malloc()'d string,
  * similar to the POSIX dirname() function but thread-safe. */
 char *
@@ -408,15 +537,31 @@ dir_name(const char *file_name)
     while (len > 0 && file_name[len - 1] == '/') {
         len--;
     }
-    if (!len) {
-        return xstrdup((file_name[0] == '/'
-                        && file_name[1] == '/'
-                        && file_name[2] != '/') ? "//"
-                       : file_name[0] == '/' ? "/"
-                       : ".");
-    } else {
-        return xmemdup0(file_name, len);
+    return len ? xmemdup0(file_name, len) : all_slashes_name(file_name);
+}
+
+/* Returns the file name portion of 'file_name' as a malloc()'d string,
+ * similar to the POSIX basename() function but thread-safe. */
+char *
+base_name(const char *file_name)
+{
+    size_t end, start;
+
+    end = strlen(file_name);
+    while (end > 0 && file_name[end - 1] == '/') {
+        end--;
+    }
+
+    if (!end) {
+        return all_slashes_name(file_name);
+    }
+
+    start = end;
+    while (start > 0 && file_name[start - 1] != '/') {
+        start--;
     }
+
+    return xmemdup0(file_name + start, end - start);
 }
 
 /* If 'file_name' starts with '/', returns a copy of 'file_name'.  Otherwise,
@@ -447,7 +592,18 @@ abs_file_name(const char *dir, const char *file_name)
 
 
 /* Pass a value to this function if it is marked with
- * __attribute__((warn_unused_result)) and you genuinely want to ignore 
- * its return value.  (Note that every scalar type can be implicitly 
+ * __attribute__((warn_unused_result)) and you genuinely want to ignore
+ * 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 ");
+}