verbose: Ensure mutual exclusion when logging

[src/app-framework-binder.git] / src / verbose.c

diff --git a/src/verbose.c b/src/verbose.c
index 2b00907..e96627e 100644 (file)
--- a/src/verbose.c
+++ b/src/verbose.c
@@ -21,22 +21,27 @@
 
 #include "verbose.h"
 
+#if !defined(DEFAULT_VERBOSITY)
+# define DEFAULT_VERBOSITY Verbosity_Level_Warning
+#endif
+
 int verbosity = 1;
+void (*verbose_observer)(int loglevel, const char *file, int line, const char *function, const char *fmt, va_list args);
 
-#define LEVEL(x) ((x) < 0 ? 0 : (x) > 7 ? 7 : (x))
+#define CROP_LOGLEVEL(x) ((x) < Log_Level_Emergency ? Log_Level_Emergency : (x) > Log_Level_Debug ? Log_Level_Debug : (x))
 
 #if defined(VERBOSE_WITH_SYSLOG)
 
 #include <syslog.h>
 
-void vverbose(int level, const char *file, int line, const char *function, const char *fmt, va_list args)
+static void _vverbose_(int loglevel, const char *file, int line, const char *function, const char *fmt, va_list args)
 {
        char *p;
 
        if (file == NULL || vasprintf(&p, fmt, args) < 0)
-               vsyslog(level, fmt, args);
+               vsyslog(loglevel, fmt, args);
        else {
-               syslog(LEVEL(level), "%s [%s:%d, function]", p, file, line, function);
+               syslog(CROP_LOGLEVEL(loglevel), "%s [%s:%d, function]", p, file, line, function);
                free(p);
        }
 }
@@ -56,15 +61,15 @@ static const char *appname;
 
 static int appauthority;
 
-void vverbose(int level, const char *file, int line, const char *function, const char *fmt, va_list args)
+static void _vverbose_(int loglevel, const char *file, int line, const char *function, const char *fmt, va_list args)
 {
        char lino[20];
 
        if (file == NULL) {
-               sd_journal_printv(level, fmt, args);
+               sd_journal_printv(loglevel, fmt, args);
        } else {
                sprintf(lino, "%d", line);
-               sd_journal_printv_with_location(level, file, lino, function, fmt, args);
+               sd_journal_printv_with_location(loglevel, file, lino, function, fmt, args);
        }
 }
 
@@ -78,6 +83,9 @@ void verbose_set_name(const char *name, int authority)
 
 #include <unistd.h>
 #include <errno.h>
+#include <string.h>
+#include <sys/uio.h>
+#include <pthread.h>
 
 static const char *appname;
 
@@ -94,18 +102,81 @@ static const char *prefixes[] = {
        "<7> DEBUG"
 };
 
-void vverbose(int level, const char *file, int line, const char *function, const char *fmt, va_list args)
+static int tty;
+
+static const char chars[] = { '\n', '?', ':', ' ', '[', ',', ']' };
+
+static pthread_mutex_t mutex = PTHREAD_MUTEX_INITIALIZER;
+
+static void _vverbose_(int loglevel, const char *file, int line, const char *function, const char *fmt, va_list args)
 {
-       int saverr = errno;
-       int tty = isatty(fileno(stderr));
-       errno = saverr;
+       char buffer[4000];
+       char lino[40];
+       int saverr, n, rc;
+       struct iovec iov[20];
+
+       saverr = errno;
+
+       if (!tty)
+               tty = 1 + isatty(STDERR_FILENO);
+
+       iov[0].iov_base = (void*)prefixes[CROP_LOGLEVEL(loglevel)] + (tty - 1 ? 4 : 0);
+       iov[0].iov_len = strlen(iov[0].iov_base);
+
+       iov[1].iov_base = (void*)&chars[2];
+       iov[1].iov_len = 2;
+
+       n = 2;
+       if (fmt) {
+               iov[n].iov_base = buffer;
+               errno = saverr;
+               rc = vsnprintf(buffer, sizeof buffer, fmt, args);
+               if (rc < 0)
+                       rc = 0;
+               else if ((size_t)rc > sizeof buffer) {
+                       rc = (int)sizeof buffer;
+                       buffer[rc - 1] = buffer[rc - 2]  = buffer[rc - 3] = '.';
+               }
+               iov[n++].iov_len = (size_t)rc;
+       }
+       if (file && (!fmt || tty == 1 || loglevel <= Log_Level_Warning)) {
+               iov[n].iov_base = (void*)&chars[3 + !fmt];
+               iov[n++].iov_len = 2 - !fmt;
+               iov[n].iov_base = (void*)file;
+               iov[n++].iov_len = strlen(file);
+               iov[n].iov_base = (void*)&chars[2];
+               iov[n++].iov_len = 1;
+               if (line) {
+                       iov[n].iov_base = lino;
+                       iov[n++].iov_len = snprintf(lino, sizeof lino, "%d", line);
+               } else {
+                       iov[n].iov_base = (void*)&chars[1];
+                       iov[n++].iov_len = 1;
+               }
+               iov[n].iov_base = (void*)&chars[5];
+               iov[n++].iov_len = 1;
+               if (function) {
+                       iov[n].iov_base = (void*)function;
+                       iov[n++].iov_len = strlen(function);
+               } else {
+                       iov[n].iov_base = (void*)&chars[1];
+                       iov[n++].iov_len = 1;
+               }
+               iov[n].iov_base = (void*)&chars[6];
+               iov[n++].iov_len = 1;
+       }
+       if (n == 2) {
+               iov[n].iov_base = (void*)&chars[1];
+               iov[n++].iov_len = 1;
+       }
+       iov[n].iov_base = (void*)&chars[0];
+       iov[n++].iov_len = 1;
 
-       fprintf(stderr, "%s: ", prefixes[LEVEL(level)] + (tty ? 4 : 0));
-       vfprintf(stderr, fmt, args);
-       if (file != NULL && (!tty || verbosity > 2))
-               fprintf(stderr, " [%s:%d,%s]\n", file, line, function);
-       else
-               fprintf(stderr, "\n");
+       pthread_mutex_lock(&mutex);
+       writev(STDERR_FILENO, iov, n);
+       pthread_mutex_unlock(&mutex);
+
+       errno = saverr;
 }
 
 void verbose_set_name(const char *name, int authority)
@@ -116,12 +187,27 @@ void verbose_set_name(const char *name, int authority)
 
 #endif
 
-void verbose(int level, const char *file, int line, const char *function, const char *fmt, ...)
+void verbose(int loglevel, const char *file, int line, const char *function, const char *fmt, ...)
 {
        va_list ap;
 
        va_start(ap, fmt);
-       vverbose(level, file, line, function, fmt, ap);
+       vverbose(loglevel, file, line, function, fmt, ap);
        va_end(ap);
 }
 
+void vverbose(int loglevel, const char *file, int line, const char *function, const char *fmt, va_list args)
+{
+       void (*observer)(int loglevel, const char *file, int line, const char *function, const char *fmt, va_list args) = verbose_observer;
+
+       if (!observer)
+               _vverbose_(loglevel, file, line, function, fmt, args);
+       else {
+               va_list ap;
+               va_copy(ap, args);
+               _vverbose_(loglevel, file, line, function, fmt, args);
+               observer(loglevel, file, line, function, fmt, ap);
+               va_end(ap);
+       }
+}
+