src/src/debug.c

   1 /*************************************************
   2 *     Exim - an Internet mail transport agent    *
   3 *************************************************/
   4
   5 /* Copyright (c) University of Cambridge 1995 - 2009 */
   6 /* See the file NOTICE for conditions of use and distribution. */
   7
   8
   9 #include "exim.h"
  10
  11 static uschar  debug_buffer[2048];
  12 static uschar *debug_ptr = debug_buffer;
  13 static int     debug_prefix_length = 0;
  14
  15
  16
  17 /*************************************************
  18 *               Print tree                       *
  19 *************************************************/
  20
  21 /* Recursive tree-printing subroutine. It uses a static vector of uschar to
  22 hold the line-drawing characters that need to be printed on every line as it
  23 moves down the page. This function is used only in debugging circumstances. The
  24 output is done via debug_printf(). */
  25
  26 #define tree_printlinesize 132   /* line size for printing */
  27 static uschar tree_printline[tree_printlinesize];
  28
  29 /* Internal recursive subroutine.
  30
  31 Arguments:
  32   p          tree node
  33   pos        amount of indenting & vertical bars to pring
  34   barswitch  if TRUE print | at the pos value
  35
  36 Returns:     nothing
  37 */
  38
  39 static void
  40 tree_printsub(tree_node *p, int pos, int barswitch)
  41 {
  42 int i;
  43 if (p->right != NULL) tree_printsub(p->right, pos+2, 1);
  44 for (i = 0; i <= pos-1; i++) debug_printf("%c", tree_printline[i]);
  45 debug_printf("-->%s [%d]\n", p->name, p->balance);
  46 tree_printline[pos] = barswitch? '|' : ' ';
  47 if (p->left != NULL)
  48   {
  49   tree_printline[pos+2] = '|';
  50   tree_printsub(p->left, pos+2, 0);
  51   }
  52 }
  53
  54 /* The external function, with just a tree node argument. */
  55
  56 void
  57 debug_print_tree(tree_node *p)
  58 {
  59 int i;
  60 for (i = 0; i < tree_printlinesize; i++) tree_printline[i] = ' ';
  61 if (p == NULL) debug_printf("Empty Tree\n"); else tree_printsub(p, 0, 0);
  62 debug_printf("---- End of tree ----\n");
  63 }
  64
  65
  66
  67 /*************************************************
  68 *          Print an argv vector                  *
  69 *************************************************/
  70
  71 /* Called when about to obey execv().
  72
  73 Argument:    the argv vector
  74 Returns:     nothing
  75 */
  76
  77 void
  78 debug_print_argv(const uschar ** argv)
  79 {
  80 debug_printf("exec");
  81 while (*argv != NULL) debug_printf(" %.256s", *argv++);
  82 debug_printf("\n");
  83 }
  84
  85
  86
  87 /*************************************************
  88 *      Expand and print debugging string         *
  89 *************************************************/
  90
  91 /* The string is expanded and written as debugging output. If
  92 expansion fails, a message is written instead.
  93
  94 Argument:    the string
  95 Returns:     nothing
  96 */
  97
  98 void
  99 debug_print_string(uschar *debug_string)
 100 {
 101 if (debug_string == NULL) return;
 102 HDEBUG(D_any|D_v)
 103   {
 104   uschar *s = expand_string(debug_string);
 105   if (s == NULL)
 106     debug_printf("failed to expand debug_output \"%s\": %s\n", debug_string,
 107       expand_string_message);
 108   else if (s[0] != 0)
 109     debug_printf("%s%s", s, (s[Ustrlen(s)-1] == '\n')? "" : "\n");
 110   }
 111 }
 112
 113
 114
 115 /*************************************************
 116 *      Print current uids and gids               *
 117 *************************************************/
 118
 119 /*
 120 Argument:   an introductory string
 121 Returns:    nothing
 122 */
 123
 124 void
 125 debug_print_ids(uschar *s)
 126 {
 127 debug_printf("%s uid=%ld gid=%ld euid=%ld egid=%ld\n", s,
 128   (long int)getuid(), (long int)getgid(), (long int)geteuid(),
 129   (long int)getegid());
 130 }
 131
 132
 133
 134
 135 /*************************************************
 136 *           Print debugging message              *
 137 *************************************************/
 138
 139 /* There are two entries, one for use when being called directly from a
 140 function with a variable argument list.
 141
 142 If debug_pid is nonzero, print the pid at the start of each line. This is for
 143 tidier output when running parallel remote deliveries with debugging turned on.
 144 Must do the whole thing with a single printf and flush, as otherwise output may
 145 get interleaved. Since some calls to debug_printf() don't end with newline,
 146 we save up the text until we do get the newline. */
 147
 148 void
 149 debug_printf(const char *format, ...)
 150 {
 151 va_list ap;
 152 va_start(ap, format);
 153 debug_vprintf(format, ap);
 154 va_end(ap);
 155 }
 156
 157 void
 158 debug_vprintf(const char *format, va_list ap)
 159 {
 160 if (debug_file == NULL) return;
 161
 162 /* Various things can be inserted at the start of a line. Don't use the
 163 tod_stamp() function for the timestamp, because that will overwrite the
 164 timestamp buffer, which may contain something useful. (This was a bug fix: the
 165 +memory debugging with +timestamp did cause a problem.) */
 166
 167 if (debug_ptr == debug_buffer)
 168   {
 169   DEBUG(D_timestamp)
 170     {
 171     time_t now = time(NULL);
 172     struct tm *t = timestamps_utc? gmtime(&now) : localtime(&now);
 173     (void) sprintf(CS debug_ptr, "%02d:%02d:%02d ", t->tm_hour, t->tm_min,
 174       t->tm_sec);
 175     while(*debug_ptr != 0) debug_ptr++;
 176     }
 177
 178   DEBUG(D_pid)
 179     {
 180     sprintf(CS debug_ptr, "%5d ", (int)getpid());
 181     while(*debug_ptr != 0) debug_ptr++;
 182     }
 183
 184   /* Set up prefix if outputting for host checking and not debugging */
 185
 186   if (host_checking && debug_selector == 0)
 187     {
 188     Ustrcpy(debug_ptr, ">>> ");
 189     debug_ptr += 4;
 190     }
 191
 192   debug_prefix_length = debug_ptr - debug_buffer;
 193   }
 194
 195 /* Use the checked formatting routine to ensure that the buffer
 196 does not overflow. Ensure there's space for a newline at the end. */
 197
 198 if (!string_vformat(debug_ptr,
 199      sizeof(debug_buffer) - (debug_ptr - debug_buffer) - 1, format, ap))
 200   {
 201   uschar *s = US"**** debug string too long - truncated ****\n";
 202   uschar *p = debug_buffer + Ustrlen(debug_buffer);
 203   int maxlen = sizeof(debug_buffer) - Ustrlen(s) - 3;
 204   if (p > debug_buffer + maxlen) p = debug_buffer + maxlen;
 205   if (p > debug_buffer && p[-1] != '\n') *p++ = '\n';
 206   Ustrcpy(p, s);
 207   }
 208
 209 while(*debug_ptr != 0) debug_ptr++;
 210
 211 /* Output the line if it is complete. If we added any prefix data and there
 212 are internal newlines, make sure the prefix is on the continuation lines,
 213 as long as there is room in the buffer. We want to do just a single fprintf()
 214 so as to avoid interleaving. */
 215
 216 if (debug_ptr[-1] == '\n')
 217   {
 218   if (debug_prefix_length > 0)
 219     {
 220     uschar *p = debug_buffer;
 221     int left = sizeof(debug_buffer) - (debug_ptr - debug_buffer) - 1;
 222     while ((p = Ustrchr(p, '\n') + 1) != debug_ptr &&
 223            left >= debug_prefix_length)
 224       {
 225       int len = debug_ptr - p;
 226       memmove(p + debug_prefix_length, p, len + 1);
 227       memmove(p, debug_buffer, debug_prefix_length);
 228       debug_ptr += debug_prefix_length;
 229       left -= debug_prefix_length;
 230       }
 231     }
 232
 233   fprintf(debug_file, "%s", CS debug_buffer);
 234   fflush(debug_file);
 235   debug_ptr = debug_buffer;
 236   debug_prefix_length = 0;
 237   }
 238 }
 239
 240 /* End of debug.c */