From 1365950c01a87e8ede70da4d3937d379e3050d13 Mon Sep 17 00:00:00 2001 From: hniksic Date: Sun, 9 Dec 2001 21:31:45 -0800 Subject: [PATCH] [svn] Logging system bugfixes and improvements. Published in . --- src/ChangeLog | 31 ++++++++ src/log.c | 199 ++++++++++++++++++++++++++++++++++-------------- src/main.c | 26 +++---- src/mswindows.c | 7 +- src/progress.c | 2 + src/utils.c | 29 +++---- src/wget.h | 1 + 7 files changed, 201 insertions(+), 94 deletions(-) diff --git a/src/ChangeLog b/src/ChangeLog index 5edfcb7b..6feff5c3 100644 --- a/src/ChangeLog +++ b/src/ChangeLog @@ -1,3 +1,34 @@ +2001-12-10 Hrvoje Niksic + + * main.c (main): Initialize progress after fork_to_background, so + that it knows when to use dots. + + * mswindows.c (ws_hangup): Call log_request_redirect_output. + + * utils.c (fork_to_background): Print the PID of the child + process. + + * log.c (log_request_redirect_output): Set a flag that output + redirection has been requested. Doing anything else in a signal + handler is unsafe. + (check_redirect_output): New function: check whether redirection + has been requested and, if so, call redirect_output(). + (logputs): Call check_redirect_output. + (logprintf): Ditto. + (debug_logprintf): Ditto. + (redirect_output): Print clearer messages. + + * main.c (redirect_output_signal): Don't call + redirect_output_signal directly. Instead, call + log_request_redirect_output. + + * utils.c (memfatal): Ditto. + + * progress.c (display_image): Use it. + + * log.c (log_set_save_context): New function: allow the caller to + turn off saving log context lines. + 2001-12-10 Hrvoje Niksic * host.c (address_list_set_faulty): Uncomment a sanity check. diff --git a/src/log.c b/src/log.c index f79c5eb4..aa38348b 100644 --- a/src/log.c +++ b/src/log.c @@ -44,16 +44,43 @@ Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ #ifndef errno extern int errno; #endif - -/* The file descriptor used for logging. */ +/* This file impplement support for "logging". Logging means printing + output, plus several additional features: + + - Cataloguing output by importance. You can specify that a log + message is "verbose" or "debug", and it will not be printed unless + in verbose or debug mode, respectively. + + - Redirecting the log to the file. When Wget's output goes to the + terminal, and Wget receives SIGHUP, all further output is + redirected to a log file. When this is the case, Wget can also + print the last several lines of "context" to the log file so that + it does not begin in the middle of a line. For this to work, the + logging code stores the last several lines of context. Callers may + request for certain output not to be stored. + + - Inhibiting output. When Wget receives SIGHUP, but redirecting + the output fails, logging is inhibited. */ + + +/* The file descriptor used for logging. This is NULL before log_init + is called; logging functions log to stderr then. log_init sets it + either to stderr or to a file pointer obtained from fopen(). If + logging is inhibited, logfp is set back to NULL. */ static FILE *logfp; -/* Whether logging is saved at all. */ -int save_log_p; +/* If non-zero, it means logging is inhibited, i.e. nothing is printed + or stored. */ +static int inhibit_logging; + +/* Whether the last output lines are stored for use as context. */ +static int save_context_p; /* Whether the log is flushed after each command. */ static int flush_log_p = 1; + +/* Whether any output has been received while flush_log_p was 0. */ static int needs_flushing; /* In the event of a hang-up, and if its output was on a TTY, Wget @@ -72,13 +99,13 @@ static int needs_flushing; The problem here is that we'd have to either (re)allocate and free strings all the time, or limit the lines to an arbitrary number of characters. Instead of settling for either of these, we do both: - if the line is smaller than a certain "usual" line length (80 chars - by default), a preallocated memory is used. The rare lines that - are longer than 80 characters are malloc'ed and freed separately. - This gives good performance with minimum memory consumption and - fragmentation. */ + if the line is smaller than a certain "usual" line length (128 + chars by default), a preallocated memory is used. The rare lines + that are longer than 128 characters are malloc'ed and freed + separately. This gives good performance with minimum memory + consumption and fragmentation. */ -#define STATIC_LENGTH 80 +#define STATIC_LENGTH 128 static struct log_ln { char static_line[STATIC_LENGTH + 1]; /* statically allocated @@ -100,6 +127,7 @@ static int log_line_current = -1; than create new ones. */ static int trailing_line; +static void check_redirect_output PARAMS ((void)); #define ROT_ADVANCE(num) do { \ if (++num >= SAVED_LOG_LINES) \ @@ -252,15 +280,21 @@ saved_append (const char *s) return; \ } -#define CANONICALIZE_LOGFP_OR_RETURN do { \ - if (logfp == stdin) \ - return; \ - else if (!logfp) \ - /* This might happen if somebody calls a */ \ - /* log* function before log_init(). */ \ - logfp = stderr; \ -} while (0) +/* Returns the file descriptor for logging. This is LOGFP, except if + called before log_init, in which case it returns stderr. This is + useful in case someone calls a logging function before log_init. + If logging is inhibited, return NULL. */ + +static FILE * +get_log_fp (void) +{ + if (inhibit_logging) + return NULL; + if (logfp) + return logfp; + return stderr; +} /* Log a literal string S. The string is logged as-is, without a newline appended. */ @@ -268,13 +302,15 @@ saved_append (const char *s) void logputs (enum log_options o, const char *s) { - CHECK_VERBOSE (o); - CANONICALIZE_LOGFP_OR_RETURN; + FILE *fp; - fputs (s, logfp); - if (save_log_p) + check_redirect_output (); + if (!(fp = get_log_fp ())) + return; + + fputs (s, fp); + if (save_context_p) saved_append (s); - if (flush_log_p) logflush (); else @@ -288,7 +324,7 @@ struct logvprintf_state { }; /* Print a message to the log. A copy of message will be saved to - saved_log, for later reusal by log_dump(). + saved_log, for later reusal by log_dump_context(). It is not possible to code this function in a "natural" way, using a loop, because of the braindeadness of the varargs API. @@ -304,12 +340,13 @@ logvprintf (struct logvprintf_state *state, const char *fmt, va_list args) char *write_ptr = smallmsg; int available_size = sizeof (smallmsg); int numwritten; + FILE *fp = get_log_fp (); - if (!save_log_p) + if (!save_context_p) { /* In the simple case just call vfprintf(), to avoid needless allocation and games with vsnprintf(). */ - vfprintf (logfp, fmt, args); + vfprintf (fp, fmt, args); goto flush; } @@ -356,7 +393,7 @@ logvprintf (struct logvprintf_state *state, const char *fmt, va_list args) /* Writing succeeded. */ saved_append (write_ptr); - fputs (write_ptr, logfp); + fputs (write_ptr, fp); if (state->bigmsg) xfree (state->bigmsg); @@ -373,8 +410,9 @@ logvprintf (struct logvprintf_state *state, const char *fmt, va_list args) void logflush (void) { - CANONICALIZE_LOGFP_OR_RETURN; - fflush (logfp); + FILE *fp = get_log_fp (); + if (fp) + fflush (fp); needs_flushing = 0; } @@ -400,6 +438,18 @@ log_set_flush (int flush) } } +/* (Temporarily) disable storing log to memory. Returns the old + status of storing, with which this function can be called again to + reestablish storing. */ + +int +log_set_save_context (int savep) +{ + int old = save_context_p; + save_context_p = savep; + return old; +} + #ifdef WGET_USE_STDARG # define VA_START_1(arg1_type, arg1, args) va_start(args, arg1) # define VA_START_2(arg1_type, arg1, arg2_type, arg2, args) va_start(args, arg2) @@ -440,8 +490,10 @@ logprintf (va_alist) va_end (args); #endif + check_redirect_output (); + if (inhibit_logging) + return; CHECK_VERBOSE (o); - CANONICALIZE_LOGFP_OR_RETURN; memset (&lpstate, '\0', sizeof (lpstate)); do @@ -474,7 +526,9 @@ debug_logprintf (va_alist) struct logvprintf_state lpstate; int done; - CANONICALIZE_LOGFP_OR_RETURN; + check_redirect_output (); + if (inhibit_logging) + return; memset (&lpstate, '\0', sizeof (lpstate)); do @@ -512,7 +566,7 @@ log_init (const char *file, int appendp) easier on the user. */ logfp = stderr; - /* If the output is a TTY, enable logging, which will make Wget + /* If the output is a TTY, enable storing, which will make Wget remember all the printed messages, to be able to dump them to a log file in case SIGHUP or SIGUSR1 is received (or Ctrl+Break is pressed under Windows). */ @@ -522,7 +576,7 @@ log_init (const char *file, int appendp) #endif ) { - save_log_p = 1; + save_context_p = 1; } } } @@ -534,9 +588,12 @@ log_close (void) { int i; - if (logfp != stdin) + if (logfp) fclose (logfp); - save_log_p = 0; + logfp = NULL; + inhibit_logging = 1; + save_context_p = 0; + for (i = 0; i < SAVED_LOG_LINES; i++) free_log_line (i); log_line_current = -1; @@ -545,10 +602,12 @@ log_close (void) /* Dump saved lines to logfp. */ static void -log_dump (void) +log_dump_context (void) { int num = log_line_current; - FILE *fp = logfp; + FILE *fp = get_log_fp (); + if (!fp) + return; if (num == -1) return; @@ -567,33 +626,61 @@ log_dump (void) fputs (log_lines[log_line_current].content, fp); fflush (fp); } + +/* When SIGHUP or SIGUSR1 are received, the output is redirected + elsewhere. Such redirection is only allowed once. */ +enum { RR_NONE, RR_REQUESTED, RR_DONE } redirect_request = RR_NONE; +static const char *redirect_request_signal_name; -/* Redirect output to `wget-log'. MESSIJ is printed on stdout, and - should contain *exactly one* `%s', which will be replaced by the - log file name. +/* Redirect output to `wget-log'. */ - If logging was not enabled, MESSIJ will not be printed. */ -void -redirect_output (const char *messij) +static void +redirect_output (void) { - char *logfile; - - if (!save_log_p) - return; - - logfile = unique_name (DEFAULT_LOGFILE); + char *logfile = unique_name (DEFAULT_LOGFILE); + fprintf (stderr, _("\n%s received, redirecting output to `%s'.\n"), + redirect_request_signal_name, logfile); logfp = fopen (logfile, "w"); if (!logfp) { /* Eek! Opening the alternate log file has failed. Nothing we can do but disable printing completely. */ - fprintf (stderr, "%s: %s: %s\n", exec_name, logfile, strerror (errno)); - /* `stdin' is magic to not print anything, ever. */ - logfp = stdin; + fprintf (stderr, _("%s: %s; disabling logging.\n"), + logfile, strerror (errno)); + inhibit_logging = 1; + } + else + { + /* Dump the context output to the newly opened log. */ + log_dump_context (); } - fprintf (stderr, messij, logfile); xfree (logfile); - /* Dump the previous screenful of output to LOGFILE. */ - log_dump (); - save_log_p = 0; + save_context_p = 0; +} + +/* Check whether a signal handler requested the output to be + redirected. */ + +static void +check_redirect_output (void) +{ + if (redirect_request == RR_REQUESTED) + { + redirect_request = RR_DONE; + redirect_output (); + } +} + +/* Request redirection at a convenient time. This may be called from + a signal handler. */ + +void +log_request_redirect_output (const char *signal_name) +{ + if (redirect_request == RR_NONE && save_context_p) + /* Request output redirection. The request will be processed by + check_redirect_output(), which is called from entry point log + functions. */ + redirect_request = RR_REQUESTED; + redirect_request_signal_name = signal_name; } diff --git a/src/main.c b/src/main.c index 765ee737..aef78bf5 100644 --- a/src/main.c +++ b/src/main.c @@ -75,7 +75,7 @@ struct options opt; /* From log.c. */ void log_init PARAMS ((const char *, int)); void log_close PARAMS ((void)); -void redirect_output PARAMS ((const char *)); +void log_request_redirect_output PARAMS ((const char *)); static RETSIGTYPE redirect_output_signal PARAMS ((int)); @@ -679,11 +679,6 @@ GNU General Public License for more details.\n")); } } - /* Initialize progress. Have to do this after the options are - processed so we know where the log file is. */ - if (opt.verbose) - set_progress_implementation (opt.progress_type); - /* All user options have now been processed, so it's now safe to do interoption dependency checks. */ @@ -731,6 +726,11 @@ Can't timestamp and not clobber old files at the same time.\n")); if (opt.background) fork_to_background (); + /* Initialize progress. Have to do this after the options are + processed so we know where the log file is. */ + if (opt.verbose) + set_progress_implementation (opt.progress_type); + /* Allocate basic pointer. */ url = ALLOCA_ARRAY (char *, nurl + 1); /* Fill in the arguments. */ @@ -886,15 +886,11 @@ Can't timestamp and not clobber old files at the same time.\n")); static RETSIGTYPE redirect_output_signal (int sig) { - char tmp[100]; - signal (sig, redirect_output_signal); - /* Please note that the double `%' in `%%s' is intentional, because - redirect_output passes tmp through printf. */ - sprintf (tmp, _("%s received, redirecting output to `%%s'.\n"), - (sig == SIGHUP ? "SIGHUP" : - (sig == SIGUSR1 ? "SIGUSR1" : - "WTF?!"))); - redirect_output (tmp); + char *signal_name = (sig == SIGHUP ? "SIGHUP" : + (sig == SIGUSR1 ? "SIGUSR1" : + "WTF?!")); + log_request_redirect_output (signal_name); progress_schedule_redirect (); + signal (sig, redirect_output_signal); } #endif /* HAVE_SIGNAL */ diff --git a/src/mswindows.c b/src/mswindows.c index 6353cc28..f10c6123 100644 --- a/src/mswindows.c +++ b/src/mswindows.c @@ -36,7 +36,7 @@ extern int errno; #endif /* Defined in log.c. */ -void redirect_output (const char *); +void log_request_redirect_output PARAMS ((const char *)); static int windows_nt_p; @@ -103,10 +103,7 @@ ws_cleanup (void) static void ws_hangup (void) { - redirect_output (_("\n\ -CTRL+Break received, redirecting output to `%s'.\n\ -Execution continued in background.\n\ -You may stop Wget by pressing CTRL+ALT+DELETE.\n")); + log_request_redirect_output ("CTRL+Break"); } void diff --git a/src/progress.c b/src/progress.c index 3ae5b38d..dc967636 100644 --- a/src/progress.c +++ b/src/progress.c @@ -683,8 +683,10 @@ create_image (struct bar_progress *bp, long dltime) static void display_image (char *buf) { + int old = log_set_save_context (0); logputs (LOG_VERBOSE, "\r"); logputs (LOG_VERBOSE, buf); + log_set_save_context (old); } static void diff --git a/src/utils.c b/src/utils.c index 3e8b466e..2c6fd784 100644 --- a/src/utils.c +++ b/src/utils.c @@ -84,21 +84,9 @@ extern int errno; static void memfatal (const char *what) { - /* HACK: expose save_log_p from log.c, so we can turn it off in - order to prevent saving the log. Saving the log is dangerous - because logprintf() and logputs() can call malloc(), so this - could infloop. When logging is turned off, infloop can no longer - happen. - - #### This is no longer really necessary because the new routines - in log.c cons only if the line exceeds eighty characters. But - this can come at the end of a line, so it's OK to be careful. - - On a more serious note, it would be good to have a - log_forced_shutdown() routine that exposes this cleanly. */ - extern int save_log_p; - - save_log_p = 0; + /* Make sure we don't try to store part of the log line, and thus + call malloc. */ + log_set_save_context (0); logprintf (LOG_ALWAYS, _("%s: %s: Not enough memory.\n"), exec_name, what); exit (1); } @@ -464,12 +452,17 @@ fork_to_background (void) else if (pid != 0) { /* parent, no error */ - printf (_("Continuing in background.\n")); + printf (_("Continuing in background, pid %d.\n"), (int)pid); if (changedp) printf (_("Output will be written to `%s'.\n"), opt.lfilename); - exit (0); + exit (0); /* #### should we use _exit()? */ } - /* child: keep running */ + + /* child: give up the privileges and keep running. */ + setsid (); + freopen ("/dev/null", "r", stdin); + freopen ("/dev/null", "w", stdout); + freopen ("/dev/null", "w", stderr); } #endif /* not WINDOWS */ diff --git a/src/wget.h b/src/wget.h index a1f737a4..fe57639f 100644 --- a/src/wget.h +++ b/src/wget.h @@ -105,6 +105,7 @@ void debug_logprintf (); void logputs PARAMS ((enum log_options, const char *)); void logflush PARAMS ((void)); void log_set_flush PARAMS ((int)); +int log_set_save_context PARAMS ((int)); /* Defined in `utils.c', but used literally everywhere. */ #ifndef DEBUG_MALLOC