1 #include <stdio.h>

2 #include <stdlib.h>

3 #include <string.h>

4 #include <errno.h>

5 #include <stdarg.h>

6 #include "log.h"

7

8 void sgl_log(const char *fmt, ...)

9 {

10 static int first_run = 1;

11 va_list ap;

12 const char *logfile;

13 FILE *fp;

14

15 if((logfile = getenv("SGL_LOG"))) {

16 if(first_run) {

17 remove(logfile);

18 first_run = 0;

19 }

20 if(!(fp = fopen(logfile, "a"))) {

21 fprintf(stderr, "failed to open logfile: %s: %s\n", logfile, strerror(errno));

22 fp = stderr;

23 }

24 } else {

25 fp = stderr;

26 }

27

28 va_start(ap, fmt);

29 vfprintf(fp, fmt, ap);

30 va_end(ap);

31

32 if(fp != stderr) {

33 fclose(fp);

34 }

35 }