debug: Add support for log files

A new command line argument --logfile or -l is now supported for
logging purposes.

Signed-off-by: Timo Kokkonen <timo.t.kokkonen@iki.fi>

diff --git a/debug.c b/debug.c
index 6c7042eda7af35cb91e2c0dd3c321afca9c08c7b..55fdd14937c8dd9d7080584b60a093412e5d5bef 100644 (file)
--- a/debug.c
+++ b/debug.c
@@ -1,3 +1,6 @@
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
 #include <time.h>
 #include <unistd.h>
 #include <stdarg.h>
@@ -18,6 +21,7 @@ const char normal_color[] = {
 };
 
 int trace_level = 1;
+int logfile_fd = STDERR_FILENO;
 
 static const char *assign_color(int color)
 {
@@ -38,7 +42,9 @@ void print_trace(const char *file, int line, int color, int l,
        time_t t = time(0);
        char time[32];
        char trace[1024];
+       char all_trace[1538];
        const char *color_str = assign_color(color);
+       int ret;
 
        if (l > trace_level)
                return;
@@ -49,9 +55,36 @@ void print_trace(const char *file, int line, int color, int l,
 
        strftime(time, sizeof(time), "%d.%m.%Y %T", localtime(&t));
 
-       fprintf(stderr, "%s%s [%5d.%d] %s:%d %s %s",
+       ret = snprintf(all_trace, sizeof(all_trace),
+               "%s%s [%5d.%d] %s:%d %s %s",
                color_str, time,
                getpid(), get_parent_count(),
                file, line, normal_color, trace);
-       fflush(stderr);
+
+       ret = write(logfile_fd, all_trace, ret);
+       /*
+        * If write failed, well, not much point in trying to print a
+        * trace about it.. So we just ignore the return value
+        */
+}
+
+int open_log_file(const char *logfile)
+{
+       int fd;
+
+       pr_info("Switching logging to file: %s\n", logfile);
+
+       fd = open(logfile, O_WRONLY | O_CREAT | O_APPEND, 0666);
+       if (fd < 0) {
+               pr_err("Failed to open logfile %s: %m\n", logfile);
+               return fd;
+       }
+
+       if (logfile_fd != STDERR_FILENO)
+               close(logfile_fd);
+       logfile_fd = fd;
+
+       pr_info("Opened file %s for logging\n", logfile);
+
+       return 0;
 }

diff --git a/debug.h b/debug.h
index 54e81a2cc0fb715fa534191e2085cc8cb81b0413..1dd11f9fba370cd14a581ae95f7928ac7c57499f 100644 (file)
--- a/debug.h
+++ b/debug.h
@@ -12,4 +12,6 @@ print_trace(const char *file, int line, int color, int l,
 #define pr_err(arg...)  print_trace(__FILE__, __LINE__, 1, 0, arg)
 #define pr_info(arg...) print_trace(__FILE__, __LINE__, 2, 1, arg)
 
+int open_log_file(const char *logfile);
+
 #endif

diff --git a/main.c b/main.c
index 75eddf397076e82b0441961866f0242b3842b81b..55e1ef3fc046f349aecffa4adce7f987cb792762 100644 (file)
--- a/main.c
+++ b/main.c
@@ -25,9 +25,10 @@ int read_args(int argc, char *argv[], struct user_options *opts)
        static struct option long_options[] = {
                { .val = 'j', .has_arg = 1, .name = "jobs", },
                { .val = 'c', .has_arg = 1, .name = "config", },
+               { .val = 'l', .has_arg = 1, .name = "log-file", },
                { },
        };
-       char short_options[] = "j:c:";
+       char short_options[] = "j:c:l:";
 
        while (1) {
                c = getopt_long(argc, argv, short_options, long_options,
@@ -45,6 +46,10 @@ int read_args(int argc, char *argv[], struct user_options *opts)
                        opts->config_file = optarg;
                        break;
 
+               case 'l':
+                       open_log_file(optarg);
+                       break;
+
                case '?':
                        return -1;
                }