src/src/debug.c

   1 /* $Cambridge: exim/src/src/debug.c,v 1.6 2007/01/08 10:50:17 ph10 Exp $ */
   2
   3 /*************************************************
   4 *     Exim - an Internet mail transport agent    *
   5 *************************************************/
   6
   7 /* Copyright (c) University of Cambridge 1995 - 2007 */
   8 /* See the file NOTICE for conditions of use and distribution. */
   9
  10
  11 #include "exim.h"
  12
  13 static uschar  debug_buffer[2048];
  14 static uschar *debug_ptr = debug_buffer;
  15 static int     debug_prefix_length = 0;
  16
  17
  18
  19 /*************************************************
  20 *               Print tree                       *
  21 *************************************************/
  22
  23 /* Recursive tree-printing subroutine. It uses a static vector of uschar to
  24 hold the line-drawing characters that need to be printed on every line as it
  25 moves down the page. This function is used only in debugging circumstances. The
  26 output is done via debug_printf(). */
  27
  28 #define tree_printlinesize 132   /* line size for printing */
  29 static uschar tree_printline[tree_printlinesize];
  30
  31 /* Internal recursive subroutine.
  32
  33 Arguments:
  34   p          tree node
  35   pos        amount of indenting & vertical bars to pring
  36   barswitch  if TRUE print | at the pos value
  37
  38 Returns:     nothing
  39 */
  40
  41 static void
  42 tree_printsub(tree_node *p, int pos, int barswitch)
  43 {
  44 int i;
  45 if (p->right != NULL) tree_printsub(p->right, pos+2, 1);
  46 for (i = 0; i <= pos-1; i++) debug_printf("%c", tree_printline[i]);
  47 debug_printf("-->%s [%d]\n", p->name, p->balance);
  48 tree_printline[pos] = barswitch? '|' : ' ';
  49 if (p->left != NULL)
  50   {
  51   tree_printline[pos+2] = '|';
  52   tree_printsub(p->left, pos+2, 0);
  53   }
  54 }
  55
  56 /* The external function, with just a tree node argument. */
  57
  58 void
  59 debug_print_tree(tree_node *p)
  60 {
  61 int i;
  62 for (i = 0; i < tree_printlinesize; i++) tree_printline[i] = ' ';
  63 if (p == NULL) debug_printf("Empty Tree\n"); else tree_printsub(p, 0, 0);
  64 debug_printf("---- End of tree ----\n");
  65 }
  66
  67
  68
  69 /*************************************************
  70 *          Print an argv vector                  *
  71 *************************************************/
  72
  73 /* Called when about to obey execv().
  74
  75 Argument:    the argv vector
  76 Returns:     nothing
  77 */
  78
  79 void
  80 debug_print_argv(uschar **argv)
  81 {
  82 debug_printf("exec");
  83 while (*argv != NULL) debug_printf(" %.256s", *argv++);
  84 debug_printf("\n");
  85 }
  86
  87
  88
  89 /*************************************************
  90 *      Expand and print debugging string         *
  91 *************************************************/
  92
  93 /* The string is expanded and written as debugging output. If
  94 expansion fails, a message is written instead.
  95
  96 Argument:    the string
  97 Returns:     nothing
  98 */
  99
 100 void
 101 debug_print_string(uschar *debug_string)
 102 {
 103 if (debug_string == NULL) return;
 104 HDEBUG(D_any|D_v)
 105   {
 106   uschar *s = expand_string(debug_string);
 107   if (s == NULL)
 108     debug_printf("failed to expand debug_output \"%s\": %s\n", debug_string,
 109       expand_string_message);
 110   else if (s[0] != 0)
 111     debug_printf("%s%s", s, (s[Ustrlen(s)-1] == '\n')? "" : "\n");
 112   }
 113 }
 114
 115
 116
 117 /*************************************************
 118 *      Print current uids and gids               *
 119 *************************************************/
 120
 121 /*
 122 Argument:   an introductory string
 123 Returns:    nothing
 124 */
 125
 126 void
 127 debug_print_ids(uschar *s)
 128 {
 129 debug_printf("%s uid=%ld gid=%ld euid=%ld egid=%ld\n", s,
 130   (long int)getuid(), (long int)getgid(), (long int)geteuid(),
 131   (long int)getegid());
 132 }
 133
 134
 135
 136
 137 /*************************************************
 138 *           Print debugging message              *
 139 *************************************************/
 140
 141 /* There are two entries, one for use when being called directly from a
 142 function with a variable argument list.
 143
 144 If debug_pid is nonzero, print the pid at the start of each line. This is for
 145 tidier output when running parallel remote deliveries with debugging turned on.
 146 Must do the whole thing with a single printf and flush, as otherwise output may
 147 get interleaved. Since some calls to debug_printf() don't end with newline,
 148 we save up the text until we do get the newline. */
 149
 150 void
 151 debug_printf(char *format, ...)
 152 {
 153 va_list ap;
 154 va_start(ap, format);
 155 debug_vprintf(format, ap);
 156 va_end(ap);
 157 }
 158
 159 void
 160 debug_vprintf(char *format, va_list ap)
 161 {
 162 if (debug_file == NULL) return;
 163
 164 /* Various things can be inserted at the start of a line. Don't use the
 165 tod_stamp() function for the timestamp, because that will overwrite the
 166 timestamp buffer, which may contain something useful. (This was a bug fix: the
 167 +memory debugging with +timestamp did cause a problem.) */
 168
 169 if (debug_ptr == debug_buffer)
 170   {
 171   DEBUG(D_timestamp)
 172     {
 173     time_t now = time(NULL);
 174     struct tm *t = timestamps_utc? gmtime(&now) : localtime(&now);
 175     (void) sprintf(CS debug_ptr, "%02d:%02d:%02d ", t->tm_hour, t->tm_min,
 176       t->tm_sec);
 177     while(*debug_ptr != 0) debug_ptr++;
 178     }
 179
 180   DEBUG(D_pid)
 181     {
 182     sprintf(CS debug_ptr, "%5d ", (int)getpid());
 183     while(*debug_ptr != 0) debug_ptr++;
 184     }
 185
 186   /* Set up prefix if outputting for host checking and not debugging */
 187
 188   if (host_checking && debug_selector == 0)
 189     {
 190     Ustrcpy(debug_ptr, ">>> ");
 191     debug_ptr += 4;
 192     }
 193
 194   debug_prefix_length = debug_ptr - debug_buffer;
 195   }
 196
 197 /* Use the checked formatting routine to ensure that the buffer
 198 does not overflow. Ensure there's space for a newline at the end. */
 199
 200 if (!string_vformat(debug_ptr,
 201      sizeof(debug_buffer) - (debug_ptr - debug_buffer) - 1, format, ap))
 202   {
 203   uschar *s = US"**** debug string too long - truncated ****\n";
 204   uschar *p = debug_buffer + Ustrlen(debug_buffer);
 205   int maxlen = sizeof(debug_buffer) - Ustrlen(s) - 3;
 206   if (p > debug_buffer + maxlen) p = debug_buffer + maxlen;
 207   if (p > debug_buffer && p[-1] != '\n') *p++ = '\n';
 208   Ustrcpy(p, s);
 209   }
 210
 211 while(*debug_ptr != 0) debug_ptr++;
 212
 213 /* Output the line if it is complete. If we added any prefix data and there
 214 are internal newlines, make sure the prefix is on the continuation lines,
 215 as long as there is room in the buffer. We want to do just a single fprintf()
 216 so as to avoid interleaving. */
 217
 218 if (debug_ptr[-1] == '\n')
 219   {
 220   if (debug_prefix_length > 0)
 221     {
 222     uschar *p = debug_buffer;
 223     int left = sizeof(debug_buffer) - (debug_ptr - debug_buffer) - 1;
 224     while ((p = Ustrchr(p, '\n') + 1) != debug_ptr &&
 225            left >= debug_prefix_length)
 226       {
 227       int len = debug_ptr - p;
 228       memmove(p + debug_prefix_length, p, len + 1);
 229       memmove(p, debug_buffer, debug_prefix_length);
 230       debug_ptr += debug_prefix_length;
 231       left -= debug_prefix_length;
 232       }
 233     }
 234
 235   fprintf(debug_file, "%s", CS debug_buffer);
 236   fflush(debug_file);
 237   debug_ptr = debug_buffer;
 238   debug_prefix_length = 0;
 239   }
 240 }
 241
 242 /* End of debug.c */