+
+
+/*************************************************
+* Multi-bit set or clear *
+*************************************************/
+
+/* These functions take a list of bit indexes (terminated by -1) and
+clear or set the corresponding bits in the selector.
+
+Arguments:
+ selector address of the bit string
+ selsize number of words in the bit string
+ bits list of bits to set
+*/
+
+void
+bits_clear(unsigned int *selector, size_t selsize, int *bits)
+{
+for(; *bits != -1; ++bits)
+ BIT_CLEAR(selector, selsize, *bits);
+}
+
+void
+bits_set(unsigned int *selector, size_t selsize, int *bits)
+{
+for(; *bits != -1; ++bits)
+ BIT_SET(selector, selsize, *bits);
+}
+
+
+
+/*************************************************
+* Decode bit settings for log/debug *
+*************************************************/
+
+/* This function decodes a string containing bit settings in the form of +name
+and/or -name sequences, and sets/unsets bits in a bit string accordingly. It
+also recognizes a numeric setting of the form =<number>, but this is not
+intended for user use. It's an easy way for Exim to pass the debug settings
+when it is re-exec'ed.
+
+The option table is a list of names and bit indexes. The index -1
+means "set all bits, except for those listed in notall". The notall
+list is terminated by -1.
+
+The action taken for bad values varies depending upon why we're here.
+For log messages, or if the debugging is triggered from config, then we write
+to the log on the way out. For debug setting triggered from the command-line,
+we treat it as an unknown option: error message to stderr and die.
+
+Arguments:
+ selector address of the bit string
+ selsize number of words in the bit string
+ notall list of bits to exclude from "all"
+ string the configured string
+ options the table of option names
+ count size of table
+ which "log" or "debug"
+ flags DEBUG_FROM_CONFIG
+
+Returns: nothing on success - bomb out on failure
+*/
+
+void
+decode_bits(unsigned int *selector, size_t selsize, int *notall,
+ uschar *string, bit_table *options, int count, uschar *which, int flags)
+{
+uschar *errmsg;
+if (!string) return;
+
+if (*string == '=')
+ {
+ char *end; /* Not uschar */
+ memset(selector, 0, sizeof(*selector)*selsize);
+ *selector = strtoul(CS string+1, &end, 0);
+ if (!*end) return;
+ errmsg = string_sprintf("malformed numeric %s_selector setting: %s", which,
+ string);
+ goto ERROR_RETURN;
+ }
+
+/* Handle symbolic setting */
+
+else for(;;)
+ {
+ BOOL adding;
+ uschar *s;
+ int len;
+ bit_table *start, *end;
+
+ Uskip_whitespace(&string);
+ if (!*string) return;
+
+ if (*string != '+' && *string != '-')
+ {
+ errmsg = string_sprintf("malformed %s_selector setting: "
+ "+ or - expected but found \"%s\"", which, string);
+ goto ERROR_RETURN;
+ }
+
+ adding = *string++ == '+';
+ s = string;
+ while (isalnum(*string) || *string == '_') string++;
+ len = string - s;
+
+ start = options;
+ end = options + count;
+
+ while (start < end)
+ {
+ bit_table *middle = start + (end - start)/2;
+ int c = Ustrncmp(s, middle->name, len);
+ if (c == 0)
+ if (middle->name[len] != 0) c = -1; else
+ {
+ unsigned int bit = middle->bit;
+
+ if (bit == -1)
+ {
+ if (adding)
+ {
+ memset(selector, -1, sizeof(*selector)*selsize);
+ bits_clear(selector, selsize, notall);
+ }
+ else
+ memset(selector, 0, sizeof(*selector)*selsize);
+ }
+ else if (adding)
+ BIT_SET(selector, selsize, bit);
+ else
+ BIT_CLEAR(selector, selsize, bit);
+
+ break; /* Out of loop to match selector name */
+ }
+ if (c < 0) end = middle; else start = middle + 1;
+ } /* Loop to match selector name */
+
+ if (start >= end)
+ {
+ errmsg = string_sprintf("unknown %s_selector setting: %c%.*s", which,
+ adding? '+' : '-', len, s);
+ goto ERROR_RETURN;
+ }
+ } /* Loop for selector names */
+
+/* Handle disasters */
+
+ERROR_RETURN:
+if (Ustrcmp(which, "debug") == 0)
+ {
+ if (flags & DEBUG_FROM_CONFIG)
+ {
+ log_write(0, LOG_CONFIG|LOG_PANIC, "%s", errmsg);
+ return;
+ }
+ fprintf(stderr, "exim: %s\n", errmsg);
+ exit(EXIT_FAILURE);
+ }
+else log_write(0, LOG_CONFIG|LOG_PANIC_DIE, "%s", errmsg);
+}
+
+
+
+/*************************************************
+* Activate a debug logfile (late) *
+*************************************************/
+
+/* Normally, debugging is activated from the command-line; it may be useful
+within the configuration to activate debugging later, based on certain
+conditions. If debugging is already in progress, we return early, no action
+taken (besides debug-logging that we wanted debug-logging).
+
+Failures in options are not fatal but will result in paniclog entries for the
+misconfiguration.
+
+The first use of this is in ACL logic, "control = debug/tag=foo/opts=+expand"
+which can be combined with conditions, etc, to activate extra logging only
+for certain sources. The second use is inetd wait mode debug preservation. */
+
+void
+debug_logging_activate(uschar *tag_name, uschar *opts)
+{
+int fd = -1;
+
+if (debug_file)
+ {
+ debug_printf("DEBUGGING ACTIVATED FROM WITHIN CONFIG.\n"
+ "DEBUG: Tag=\"%s\" opts=\"%s\"\n", tag_name, opts ? opts : US"");
+ return;
+ }
+
+if (tag_name != NULL && (Ustrchr(tag_name, '/') != NULL))
+ {
+ log_write(0, LOG_MAIN|LOG_PANIC, "debug tag may not contain a '/' in: %s",
+ tag_name);
+ return;
+ }
+
+debug_selector = D_default;
+if (opts)
+ decode_bits(&debug_selector, 1, debug_notall, opts,
+ debug_options, debug_options_count, US"debug", DEBUG_FROM_CONFIG);
+
+/* When activating from a transport process we may never have logged at all
+resulting in certain setup not having been done. Hack this for now so we
+do not segfault; note that nondefault log locations will not work */
+
+if (!*file_path) set_file_path(NULL);
+
+open_log(&fd, lt_debug, tag_name);
+
+if (fd != -1)
+ debug_file = fdopen(fd, "w");
+else
+ log_write(0, LOG_MAIN|LOG_PANIC, "unable to open debug log");
+}
+
+
+void
+debug_logging_stop(void)
+{
+if (!debug_file || !debuglog_name[0]) return;
+
+debug_selector = 0;
+fclose(debug_file);
+debug_file = NULL;
+unlink_log(lt_debug);
+}
+
+/* Called from the appendfile transport setup. */
+void
+open_logs(void)
+{
+set_file_path(NULL);
+if (!(logging_mode & LOG_MODE_FILE)) return;
+open_log(&mainlogfd, lt_main, 0);
+open_log(&rejectlogfd, lt_reject, 0);
+}
+