removed clang-format and clang_complete files from the repo

[dosdemo] / src / dos / logger.c

diff --git a/src/dos/logger.c b/src/dos/logger.c
index 73860e3..1976770 100644 (file)
--- a/src/dos/logger.c
+++ b/src/dos/logger.c
@@ -1,46 +1,68 @@
-/*
-colcycle - color cycling image viewer
-Copyright (C) 2016  John Tsiombikas <nuclear@member.fsf.org>
-
-This program is free software: you can redistribute it and/or modify
-it under the terms of the GNU General Public License as published by
-the Free Software Foundation, either version 3 of the License, or
-(at your option) any later version.
-
-This program is distributed in the hope that it will be useful,
-but WITHOUT ANY WARRANTY; without even the implied warranty of
-MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-GNU General Public License for more details.
-
-You should have received a copy of the GNU General Public License
-along with this program.  If not, see <http://www.gnu.org/licenses/>.
-*/
 #include <stdio.h>
-#include <stdarg.h>
+#include <string.h>
+#include <errno.h>
+#include <unistd.h>
+#include <fcntl.h>
 #include "logger.h"
 
-#define LOGFNAME       "demo.log"
+static int logfd = -1, orig_fd1 = -1;
 
-static FILE *logfile;
+int init_logger(const char *fname)
+{
+       if(logfd != -1) return -1;
+
+       if((logfd = open(fname, O_CREAT | O_WRONLY | O_TRUNC, 0644)) == -1) {
+               fprintf(stderr, "init_logger: failed to open %s: %s\n", fname, strerror(errno));
+               return -1;
+       }
+
+       orig_fd1 = dup(1);
+       close(1);
+       close(2);
+       dup(logfd);
+       dup(logfd);
+       return 0;
+}
 
-void logger_output(FILE *fp)
+void stop_logger(void)
 {
-       if(logfile) fclose(logfile);
-       logfile = fp;
+       if(logfd >= 0) {
+               close(logfd);
+               logfd = -1;
+       }
+       if(orig_fd1 >= 0) {
+               close(1);
+               close(2);
+               dup(orig_fd1);
+               dup(orig_fd1);
+               orig_fd1 = -1;
+       }
 }
 
-void printlog(const char *fmt, ...)
+int print_tail(const char *fname)
 {
-       va_list ap;
+       FILE *fp;
+       char buf[64];
+       long lineoffs[16];
+       int wr, rd, c;
 
-       if(!logfile) {
-               if(!(logfile = fopen(LOGFNAME, "w"))) {
-                       return;
+       if(!(fp = fopen(fname, "r"))) {
+               return -1;
+       }
+       wr = rd = 0;
+       lineoffs[wr++] = 0;
+       while(fgets(buf, sizeof buf, fp)) {
+               lineoffs[wr] = ftell(fp);
+               wr = (wr + 1) & 0xf;
+               if(wr == rd) {
+                       rd = (rd + 1) & 0xf;
                }
-               setvbuf(logfile, 0, _IOLBF, 0);
        }
 
-       va_start(ap, fmt);
-       vfprintf(logfile, fmt, ap);
-       va_end(ap);
+       fseek(fp, lineoffs[rd], SEEK_SET);
+       while((c = fgetc(fp)) != -1) {
+               fputc(c, stdout);
+       }
+       fclose(fp);
+       return 0;
 }