release/src/router/pptp-client/util.c

   1 /* util.c ....... error message utilities.
   2  *                C. Scott Ananian <cananian@alumni.princeton.edu>
   3  *
   4  * $Id: util.c,v 1.11 2005/08/22 00:49:48 quozl Exp $
   5  */
   6
   7 #include <stdio.h>
   8 #include <stdarg.h>
   9 #include <syslog.h>
  10 #include <unistd.h>
  11 #include <stdlib.h>
  12 #include "util.h"
  13
  14 #ifndef PROGRAM_NAME
  15 #define PROGRAM_NAME "pptp"
  16 #endif
  17
  18 /* implementation of log_string, defined as extern in util.h */
  19 char *log_string = "anon";
  20
  21 static void open_log(void) __attribute__ ((constructor));
  22 static void close_log(void) __attribute__ ((destructor));
  23
  24 #define MAKE_STRING(label)                              \
  25 va_list ap;                                             \
  26 char buf[256], string[256];                             \
  27 va_start(ap, format);                                   \
  28 vsnprintf(buf, sizeof(buf), format, ap);                \
  29 snprintf(string, sizeof(string), "%s",  buf);           \
  30 va_end(ap)
  31
  32 /*** open log *****************************************************************/
  33 static void open_log(void) {
  34     openlog(PROGRAM_NAME, LOG_PID, LOG_DAEMON);
  35 }
  36
  37 /*** close log ****************************************************************/
  38 static void close_log(void)
  39 {
  40     closelog();
  41 }
  42
  43 /*** print a message to syslog ************************************************/
  44 void _log(const char *func, const char *file, int line, const char *format, ...)
  45 {
  46     if (log_level > 0) {
  47         MAKE_STRING("log");
  48         syslog(LOG_NOTICE, "%s", string);
  49     }
  50 }
  51
  52 /*** print a warning to syslog ************************************************/
  53 void _warn(const char *func, const char *file, int line, const char *format, ...)
  54 {
  55     MAKE_STRING("warn");
  56     fprintf(stderr, "%s\n", string);
  57     syslog(LOG_WARNING, "%s", string);
  58 }
  59
  60 /*** print a fatal warning to syslog and exit *********************************/
  61 void _fatal(const char *func, const char *file, int line, const char *format, ...)
  62 {
  63     MAKE_STRING("fatal");
  64     fprintf(stderr, "%s\n", string);
  65     syslog(LOG_CRIT, "%s", string);
  66     exit(1);
  67 }
  68
  69 /*** connect a file to a file descriptor **************************************/
  70 int file2fd(const char *path, const char *mode, int fd)
  71 {
  72     int ok = 0;
  73     FILE *file = NULL;
  74     file = fopen(path, mode);
  75     if (file != NULL && dup2(fileno(file), fd) != -1)
  76         ok = 1;
  77     if (file) fclose(file);
  78     return ok;
  79 }
  80
  81 /* signal to pipe delivery implementation */
  82 #include <unistd.h>
  83 #include <fcntl.h>
  84 #include <signal.h>
  85 #include <string.h>
  86
  87 /* pipe private to process */
  88 static int sigpipe[2];
  89
  90 /* create a signal pipe, returns 0 for success, -1 with errno for failure */
  91 int sigpipe_create()
  92 {
  93   int rc;
  94
  95   rc = pipe(sigpipe);
  96   if (rc < 0) return rc;
  97
  98   fcntl(sigpipe[0], F_SETFD, FD_CLOEXEC);
  99   fcntl(sigpipe[1], F_SETFD, FD_CLOEXEC);
 100
 101 #ifdef O_NONBLOCK
 102 #define FLAG_TO_SET O_NONBLOCK
 103 #else
 104 #ifdef SYSV
 105 #define FLAG_TO_SET O_NDELAY
 106 #else /* BSD */
 107 #define FLAG_TO_SET FNDELAY
 108 #endif
 109 #endif
 110
 111   rc = fcntl(sigpipe[1], F_GETFL);
 112   if (rc != -1)
 113     rc = fcntl(sigpipe[1], F_SETFL, rc | FLAG_TO_SET);
 114   if (rc < 0) return rc;
 115   return 0;
 116 #undef FLAG_TO_SET
 117 }
 118
 119 /* generic handler for signals, writes signal number to pipe */
 120 void sigpipe_handler(int signum)
 121 {
 122   write(sigpipe[1], &signum, sizeof(signum));
 123   signal(signum, sigpipe_handler);
 124 }
 125
 126 /* assign a signal number to the pipe */
 127 void sigpipe_assign(int signum)
 128 {
 129   struct sigaction sa;
 130
 131   memset(&sa, 0, sizeof(sa));
 132   sa.sa_handler = sigpipe_handler;
 133   sigaction(signum, &sa, NULL);
 134 }
 135
 136 /* return the signal pipe read file descriptor for select(2) */
 137 int sigpipe_fd()
 138 {
 139   return sigpipe[0];
 140 }
 141
 142 /* read and return the pending signal from the pipe */
 143 int sigpipe_read()
 144 {
 145   int signum;
 146   read(sigpipe[0], &signum, sizeof(signum));
 147   return signum;
 148 }
 149
 150 void sigpipe_close()
 151 {
 152   close(sigpipe[0]);
 153   close(sigpipe[1]);
 154 }
 155