src/src/debug.c

   1 /*************************************************
   2 *     Exim - an Internet mail transport agent    *
   3 *************************************************/
   4
   5 /* Copyright (c) University of Cambridge 1995 - 2015 */
   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 print
  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, one for prepending an indent.
 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 Take care to not disturb errno. */
 148
 149
 150 /* Debug printf indented by ACL nest depth */
 151 void
 152 debug_printf_indent(const char * format, ...)
 153 {
 154 va_list ap;
 155 va_start(ap, format);
 156 debug_vprintf(acl_level + expand_level, format, ap);
 157 va_end(ap);
 158 }
 159
 160 void
 161 debug_printf(const char *format, ...)
 162 {
 163 va_list ap;
 164 va_start(ap, format);
 165 debug_vprintf(0, format, ap);
 166 va_end(ap);
 167 }
 168
 169 void
 170 debug_vprintf(int indent, const char *format, va_list ap)
 171 {
 172 int save_errno = errno;
 173
 174 if (!debug_file) return;
 175
 176 /* Various things can be inserted at the start of a line. Don't use the
 177 tod_stamp() function for the timestamp, because that will overwrite the
 178 timestamp buffer, which may contain something useful. (This was a bug fix: the
 179 +memory debugging with +timestamp did cause a problem.) */
 180
 181 if (debug_ptr == debug_buffer)
 182   {
 183   DEBUG(D_timestamp)
 184     {
 185     struct timeval now;
 186     time_t tmp;
 187     struct tm * t;
 188
 189     gettimeofday(&now, NULL);
 190     tmp = now.tv_sec;
 191     t = timestamps_utc ? gmtime(&now) : localtime(&now);
 192     debug_ptr += sprintf(CS debug_ptr,
 193       LOGGING(millisec) ? "%02d:%02d:%02d.%03d " : "%02d:%02d:%02d ",
 194       t->tm_hour, t->tm_min, t->tm_sec, now.tv_usec/1000);
 195     }
 196
 197   DEBUG(D_pid)
 198     {
 199     debug_ptr += sprintf(CS debug_ptr, "%5d ", (int)getpid());
 200     }
 201
 202   /* Set up prefix if outputting for host checking and not debugging */
 203
 204   if (host_checking && debug_selector == 0)
 205     {
 206     Ustrcpy(debug_ptr, ">>> ");
 207     debug_ptr += 4;
 208     }
 209
 210   debug_prefix_length = debug_ptr - debug_buffer;
 211   }
 212
 213 if (indent > 0)
 214   {
 215   int i;
 216   for (i = indent >> 2; i > 0; i--)
 217     {
 218     Ustrcpy(debug_ptr, "   " UTF8_VERT_2DASH);
 219     debug_ptr += 6;     /* 3 spaces + 3 UTF-8 octets */
 220     debug_prefix_length += 6;
 221     }
 222   Ustrncpy(debug_ptr, "   ", indent &= 3);
 223   debug_ptr += indent;
 224   debug_prefix_length += indent;
 225   }
 226
 227 /* Use the checked formatting routine to ensure that the buffer
 228 does not overflow. Ensure there's space for a newline at the end. */
 229
 230 if (!string_vformat(debug_ptr,
 231      sizeof(debug_buffer) - (debug_ptr - debug_buffer) - 1, format, ap))
 232   {
 233   uschar *s = US"**** debug string too long - truncated ****\n";
 234   uschar *p = debug_buffer + Ustrlen(debug_buffer);
 235   int maxlen = sizeof(debug_buffer) - Ustrlen(s) - 3;
 236   if (p > debug_buffer + maxlen) p = debug_buffer + maxlen;
 237   if (p > debug_buffer && p[-1] != '\n') *p++ = '\n';
 238   Ustrcpy(p, s);
 239   }
 240
 241 while(*debug_ptr != 0) debug_ptr++;
 242
 243 /* Output the line if it is complete. If we added any prefix data and there
 244 are internal newlines, make sure the prefix is on the continuation lines,
 245 as long as there is room in the buffer. We want to do just a single fprintf()
 246 so as to avoid interleaving. */
 247
 248 if (debug_ptr[-1] == '\n')
 249   {
 250   if (debug_prefix_length > 0)
 251     {
 252     uschar *p = debug_buffer;
 253     int left = sizeof(debug_buffer) - (debug_ptr - debug_buffer) - 1;
 254     while ((p = Ustrchr(p, '\n') + 1) != debug_ptr &&
 255            left >= debug_prefix_length)
 256       {
 257       int len = debug_ptr - p;
 258       memmove(p + debug_prefix_length, p, len + 1);
 259       memmove(p, debug_buffer, debug_prefix_length);
 260       debug_ptr += debug_prefix_length;
 261       left -= debug_prefix_length;
 262       }
 263     }
 264
 265   fprintf(debug_file, "%s", CS debug_buffer);
 266   fflush(debug_file);
 267   debug_ptr = debug_buffer;
 268   debug_prefix_length = 0;
 269   }
 270 errno = save_errno;
 271 }
 272
 273 /* End of debug.c */