diff options
Diffstat (limited to 'exim_monitor/em_log.c')
| -rw-r--r-- | exim_monitor/em_log.c | 411 |
1 files changed, 411 insertions, 0 deletions
diff --git a/exim_monitor/em_log.c b/exim_monitor/em_log.c new file mode 100644 index 0000000..8d85c13 --- /dev/null +++ b/exim_monitor/em_log.c @@ -0,0 +1,411 @@ +/************************************************* +* Exim Monitor * +*************************************************/ + +/* Copyright (c) University of Cambridge 1995 - 2018 */ +/* Copyright (c) The Exim Maintainters 2021 - 2022 */ +/* See the file NOTICE for conditions of use and distribution. */ + +/* This module contains code for scanning the main log, +extracting information from it, and displaying a "tail". */ + +#include "em_hdr.h" + +#define log_buffer_len 4096 /* For each log entry */ + +/* If anonymizing, don't alter these strings (this is all an ad hoc hack). */ + +#ifdef ANONYMIZE +static char *oklist[] = { + "Completed", + "defer", + "from", + "Connection timed out", + "Start queue run: pid=", + "End queue run: pid=", + "host lookup did not complete", + "unexpected disconnection while reading SMTP command from", + "verify failed for SMTP recipient", + "H=", + "U=", + "id=", + "<", + ">", + "(", + ")", + "[", + "]", + "@", + "=", + "*", + ".", + "-", + "\"", + " ", + "\n"}; +static int oklist_size = sizeof(oklist) / sizeof(uschar *); +#endif + + + +/************************************************* +* Write to the log display * +*************************************************/ + +static int visible = 0; +static int scrolled = FALSE; +static int size = 0; +static int top = 0; + +static void show_log(char *s, ...) PRINTF_FUNCTION(1,2); + +static void show_log(char *s, ...) +{ +int length, newtop; +va_list ap; +XawTextBlock b; +uschar buffer[log_buffer_len + 24]; + +/* Do nothing if not tailing a log */ + +if (log_widget == NULL) return; + +/* Initialize the text block structure */ + +b.firstPos = 0; +b.ptr = CS buffer; +b.format = FMT8BIT; + +/* We want to know whether the window has been scrolled back or not, +so that we can cease automatically scrolling with new text. This turns +out to be tricky with the text widget. We can detect whether the +scroll bar has been operated by checking on the "top" value, but it's +harder to detect that it has been returned to the bottom. The following +heuristic does its best. */ + +newtop = XawTextTopPosition(log_widget); +if (newtop != top) + { + if (!scrolled) + { + visible = size - top; /* save size of window */ + scrolled = newtop < top; + } + else if (newtop > size - visible) scrolled = FALSE; + top = newtop; + } + +/* Format the text that is to be written. */ + +va_start(ap, s); +vsprintf(CS buffer, s, ap); +va_end(ap); +length = Ustrlen(buffer); + +/* If we are anonymizing for screen shots, flatten various things. */ + +#ifdef ANONYMIZE + { + uschar *p = buffer + 9; + if (p[6] == '-' && p[13] == '-') p += 17; + + while (p < buffer + length) + { + int i; + + /* Check for strings to be left alone */ + + for (i = 0; i < oklist_size; i++) + { + int len = Ustrlen(oklist[i]); + if (Ustrncmp(p, oklist[i], len) == 0) + { + p += len; + break; + } + } + if (i < oklist_size) continue; + + /* Leave driver names, size, protocol, alone */ + + if ((*p == 'D' || *p == 'P' || *p == 'T' || *p == 'S' || *p == 'R') && + p[1] == '=') + { + p += 2; + while (*p != ' ' && *p != 0) p++; + continue; + } + + /* Leave C= text alone */ + + if (Ustrncmp(p, "C=\"", 3) == 0) + { + p += 3; + while (*p != 0 && *p != '"') p++; + continue; + } + + /* Flatten remaining chars */ + + if (isdigit(*p)) *p++ = 'x'; + else if (isalpha(*p)) *p++ = 'x'; + else *p++ = '$'; + } + } +#endif + +/* If this would overflow the buffer, throw away 50% of the +current stuff in the buffer. Code defensively against odd +extreme cases that shouldn't actually arise. */ + +if (size + length > log_buffer_size) + { + if (size == 0) length = log_buffer_size/2; else + { + int cutcount = log_buffer_size/2; + if (cutcount > size) cutcount = size; else + { + while (cutcount < size && log_display_buffer[cutcount] != '\n') + cutcount++; + cutcount++; + } + b.length = 0; + XawTextReplace(log_widget, 0, cutcount, &b); + size -= cutcount; + top -= cutcount; + if (top < 0) top = 0; + if (top < cutcount) XawTextInvalidate(log_widget, 0, 999999); + xs_SetValues(log_widget, 1, "displayPosition", top); + } + } + +/* Insert the new text at the end of the buffer. */ + +b.length = length; +XawTextReplace(log_widget, 999999, 999999, &b); +size += length; + +/* When not scrolled back, we want to keep the bottom line +always visible. Put the insert point at the start of it because +this stops left/right scrolling with some X libraries. */ + +if (!scrolled) + { + XawTextSetInsertionPoint(log_widget, size - length); + top = XawTextTopPosition(log_widget); + } +} + + + + +/************************************************* +* Function to read the log * +*************************************************/ + +/* We read any new log entries, and use their data to +updated total counts for the configured stripcharts. +The count for the queue chart is handled separately. +We also munge the log entries and display a one-line +version in the log window. */ + +void read_log(void) +{ +struct stat statdata; +uschar buffer[log_buffer_len]; + +/* If log is not yet open, skip all of this. */ + +if (LOG != NULL) + { + if (fseek(LOG, log_position, SEEK_SET)) + { + perror("logfile fseek"); + exit(1); + } + + while (Ufgets(buffer, log_buffer_len, LOG) != NULL) + { + uschar *id; + uschar *p = buffer; + rmark reset_point; + int length = Ustrlen(buffer); + pcre2_match_data * md = pcre2_match_data_create(1, NULL); + + /* Skip totally blank lines (paranoia: there shouldn't be any) */ + + while (*p == ' ' || *p == '\t') p++; + if (*p == '\n') continue; + + /* We should now have a complete log entry in the buffer; check + it for various regular expression matches and take appropriate + action. Get the current store point so we can reset to it. */ + + reset_point = store_mark(); + + /* First, update any stripchart data values, noting that the zeroth + stripchart is the queue length, which is handled elsewhere, and the + 1st may the a size monitor. */ + + for (int i = stripchart_varstart; i < stripchart_number; i++) + if (pcre2_match(stripchart_regex[i], (PCRE2_SPTR)buffer, length, + 0, PCRE_EOPT, md, NULL) >= 0) + stripchart_total[i]++; + + /* Munge the log entry and display shortened form on one line. + We omit the date and show only the time. Remove any time zone offset. + Take note of the presence of [pid]. */ + + if (pcre2_match(yyyymmdd_regex, (PCRE2_SPTR) buffer, length, 0, PCRE_EOPT, + md, NULL) >= 0) + { + int pidlength = 0; + if ( (buffer[20] == '+' || buffer[20] == '-') + && isdigit(buffer[21]) && buffer[25] == ' ') + memmove(buffer + 20, buffer + 26, Ustrlen(buffer + 26) + 1); + if (buffer[20] == '[') + while (Ustrchr("[]0123456789", buffer[20+pidlength++]) != NULL) + ; + id = string_copyn(buffer + 20 + pidlength, MESSAGE_ID_LENGTH); + show_log("%s", buffer+11); + } + else + { + id = US""; + show_log("%s", buffer); + } + pcre2_match_data_free(md); + + /* Deal with frozen and unfrozen messages */ + + if (strstric(buffer, US"frozen", FALSE) != NULL) + { + queue_item *qq = find_queue(id, queue_noop, 0); + if (qq) + qq->frozen = strstric(buffer, US"unfrozen", FALSE) == NULL; + } + + /* Notice defer messages, and add the destination if it + isn't already on the list for this message, with a pointer + to the parent if we can. */ + + if ((p = Ustrstr(buffer, "==")) != NULL) + { + queue_item *qq = find_queue(id, queue_noop, 0); + if (qq) + { + dest_item *d; + uschar *q, *r; + p += 2; + while (isspace(*p)) p++; + q = p; + while (*p != 0 && !isspace(*p)) + { + if (*p++ != '\"') continue; + while (*p != 0) + { + if (*p == '\\') p += 2; + else if (*p++ == '\"') break; + } + } + *p++ = 0; + if ((r = strstric(q, qualify_domain, FALSE)) != NULL && + *(--r) == '@') *r = 0; + + /* If we already have this destination, as tested case-insensitively, + do not add it to the destinations list. */ + + d = find_dest(qq, q, dest_add, TRUE); + + if (d->parent == NULL) + { + while (isspace(*p)) p++; + if (*p == '<') + { + dest_item *dd; + q = ++p; + while (*p != 0 && *p != '>') p++; + *p = 0; + if ((p = strstric(q, qualify_domain, FALSE)) != NULL && + *(--p) == '@') *p = 0; + dd = find_dest(qq, q, dest_noop, FALSE); + if (dd != NULL && dd != d) d->parent = dd; + } + } + } + } + + store_reset(reset_point); + } + } + + +/* We have to detect when the log file is changed, and switch to the new file. +In practice, for non-datestamped files, this means that some deliveries might +go unrecorded, since they'll be written to the old file, but this usually +happens in the middle of the night, and I don't think the hassle of keeping +track of two log files is worth it. + +First we check the datestamped name of the log file if necessary; if it is +different to the file we currently have open, go for the new file. As happens +in Exim itself, we leave in the following inode check, even when datestamping +because it does no harm and will cope should a file actually be renamed for +some reason. + +The test for a changed log file is to look up the inode of the file by name and +compare it with the saved inode of the file we currently are processing. This +accords with the usual interpretation of POSIX and other Unix specs that imply +"one file, one inode". However, it appears that on some Digital systems, if an +open file is unlinked, a new file may be created with the same inode while the +old file remains in existence. This can happen if the old log file is renamed, +processed in some way, and then deleted. To work round this, also test for a +link count of zero on the currently open file. */ + +if (log_datestamping) + { + uschar log_file_wanted[256]; + /* Do *not* use "%s" here, we need the %D datestamp in the log_file string to + be expanded. The trailing NULL arg is to quieten preprocessors that need at + least one arg for a variadic set in a macro. */ + string_format(log_file_wanted, sizeof(log_file_wanted), CS log_file, NULL); + if (Ustrcmp(log_file_wanted, log_file_open) != 0) + { + if (LOG != NULL) + { + fclose(LOG); + LOG = NULL; + } + Ustrcpy(log_file_open, log_file_wanted); + } + } + +if (LOG == NULL || + (fstat(fileno(LOG), &statdata) == 0 && statdata.st_nlink == 0) || + (Ustat(log_file, &statdata) == 0 && log_inode != statdata.st_ino)) + { + FILE *TEST; + + /* Experiment shows that sometimes you can't immediately open + the new log file - presumably immediately after the old one + is renamed and before the new one exists. Therefore do a + trial open first to be sure. */ + + if ((TEST = fopen(CS log_file_open, "r")) != NULL) + { + if (LOG != NULL) fclose(LOG); + LOG = TEST; + if (fstat(fileno(LOG), &statdata)) + { + fprintf(stderr, "fstat %s: %s\n", log_file_open, strerror(errno)); + exit(1); + } + log_inode = statdata.st_ino; + } + } + +/* Save the position we have got to in the log. */ + +if (LOG != NULL) log_position = ftell(LOG); +} + +/* End of em_log.c */ |