logerr: Care about fprintf return codes

Abort early if an error and return the overall result if we ever
need it.

diff --git a/src/logerr.c b/src/logerr.c
index c2e2e1602619f58f8375e127f1a95185bed721b2..83b34bd12e165fbcd1f959126f70795e81dd65c1 100644 (file)
--- a/src/logerr.c
+++ b/src/logerr.c
@@ -92,7 +92,7 @@ getprogname(void)
 
 #ifndef SMALL
 /* Write the time, syslog style. month day time - */
-static void
+static int
 logprintdate(FILE *stream)
 {
        struct timeval tv;
@@ -101,19 +101,22 @@ logprintdate(FILE *stream)
        char buf[32];
 
        if (gettimeofday(&tv, NULL) == -1)
-               return;
+               return -1;
 
        now = tv.tv_sec;
        tzset();
-       localtime_r(&now, &tmnow);
-       strftime(buf, sizeof(buf), "%b %d %T ", &tmnow);
-       fprintf(stream, "%s", buf);
+       if (localtime_r(&now, &tmnow) == NULL)
+               return -1;
+       if (strftime(buf, sizeof(buf), "%b %d %T ", &tmnow) == 0)
+               return -1;
+       return fprintf(stream, "%s", buf);
 }
 #endif
 
-__printflike(3, 0) static void
+__printflike(3, 0) static int
 vlogprintf_r(struct logctx *ctx, FILE *stream, const char *fmt, va_list args)
 {
+       int len = 0, e;
        va_list a;
 #ifndef SMALL
        bool log_pid;
@@ -123,7 +126,11 @@ vlogprintf_r(struct logctx *ctx, FILE *stream, const char *fmt, va_list args)
 
        if ((stream == stderr && ctx->log_opts & LOGERR_ERR_DATE) ||
            (stream != stderr && ctx->log_opts & LOGERR_LOG_DATE))
-               logprintdate(stream);
+       {
+               if ((e = logprintdate(stream)) == -1)
+                       return -1;
+               len += e;
+       }
 
 #ifdef LOGERR_TAG
        log_tag = ((stream == stderr && ctx->log_opts & LOGERR_ERR_TAG) ||
@@ -131,29 +138,43 @@ vlogprintf_r(struct logctx *ctx, FILE *stream, const char *fmt, va_list args)
        if (log_tag) {
                if (ctx->log_tag == NULL)
                        ctx->log_tag = getprogname();
-               fprintf(stream, "%s", ctx->log_tag);
+               if ((e = fprintf(stream, "%s", ctx->log_tag)) == -1)
+                       return -1;
+               len += e;
        }
 #endif
 
        log_pid = ((stream == stderr && ctx->log_opts & LOGERR_ERR_PID) ||
            (stream != stderr && ctx->log_opts & LOGERR_LOG_PID));
-       if (log_pid)
-               fprintf(stream, "[%d]", getpid());
+       if (log_pid) {
+               if ((e = fprintf(stream, "[%d]", getpid())) == -1)
+                       return -1;
+               len += e;
+       }
 
 #ifdef LOGERR_TAG
        if (log_tag || log_pid)
 #else
        if (log_pid)
 #endif
-               fprintf(stream, ": ");
+       {
+               if ((e = fprintf(stream, ": ")) == -1)
+                       return -1;
+               len += e;
+       }
 #else
        UNUSED(ctx);
 #endif
 
        va_copy(a, args);
-       vfprintf(stream, fmt, a);
-       fputc('\n', stream);
+       e = vfprintf(stream, fmt, a);
+       if (fputc('\n', stream) == EOF)
+               e = -1;
+       else if (e != -1)
+               e++;
        va_end(a);
+
+       return e == -1 ? -1 : len + e;
 }
 
 /*
@@ -171,30 +192,31 @@ vlogprintf_r(struct logctx *ctx, FILE *stream, const char *fmt, va_list args)
 #pragma GCC diagnostic push
 #pragma GCC diagnostic ignored "-Wmissing-format-attribute"
 #endif
-__printflike(2, 0) static void
+__printflike(2, 0) static int
 vlogmessage(int pri, const char *fmt, va_list args)
 {
        struct logctx *ctx = &_logctx;
+       int len = 0;
 
        if (ctx->log_opts & LOGERR_ERR &&
            (pri <= LOG_ERR ||
            (!(ctx->log_opts & LOGERR_QUIET) && pri <= LOG_INFO) ||
            (ctx->log_opts & LOGERR_DEBUG && pri <= LOG_DEBUG)))
-               vlogprintf_r(ctx, stderr, fmt, args);
+               len = vlogprintf_r(ctx, stderr, fmt, args);
 
        if (!(ctx->log_opts & LOGERR_LOG))
-               return;
+               return len;
 
 #ifdef SMALL
        vsyslog(pri, fmt, args);
 #else
        if (ctx->log_file == NULL) {
                vsyslog(pri, fmt, args);
-               return;
+               return len;
        }
        if (pri == LOG_DEBUG && !(ctx->log_opts & LOGERR_DEBUG))
-               return;
-       vlogprintf_r(ctx, ctx->log_file, fmt, args);
+               return len;
+       return vlogprintf_r(ctx, ctx->log_file, fmt, args);
 #endif
 }
 #if defined(__GNUC__) && (__GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ > 5))