#ifndef errno
extern int errno;
#endif
-\f
-/* 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. */
+
+\f
+/* 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
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
than create new ones. */
static int trailing_line;
+static void check_redirect_output PARAMS ((void));
\f
#define ROT_ADVANCE(num) do { \
if (++num >= SAVED_LOG_LINES) \
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;
+}
\f
/* Log a literal string S. The string is logged as-is, without a
newline appended. */
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)
- saved_append (s);
+ 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
};
/* 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.
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;
}
/* Writing succeeded. */
saved_append (write_ptr);
- fputs (write_ptr, logfp);
+ fputs (write_ptr, fp);
if (state->bigmsg)
xfree (state->bigmsg);
void
logflush (void)
{
- CANONICALIZE_LOGFP_OR_RETURN;
- fflush (logfp);
+ FILE *fp = get_log_fp ();
+ if (fp)
+ fflush (fp);
needs_flushing = 0;
}
}
}
+/* (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)
va_end (args);
#endif
+ check_redirect_output ();
+ if (inhibit_logging)
+ return;
CHECK_VERBOSE (o);
- CANONICALIZE_LOGFP_OR_RETURN;
memset (&lpstate, '\0', sizeof (lpstate));
do
struct logvprintf_state lpstate;
int done;
- CANONICALIZE_LOGFP_OR_RETURN;
+ check_redirect_output ();
+ if (inhibit_logging)
+ return;
memset (&lpstate, '\0', sizeof (lpstate));
do
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). */
#endif
)
{
- save_log_p = 1;
+ save_context_p = 1;
}
}
}
{
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;
/* 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;
fputs (log_lines[log_line_current].content, fp);
fflush (fp);
}
+\f
+/* 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;
}
projects / wget / commitdiff