Some bug fixes

4 files changed, 153 insertions, 70 deletions

diff --git a/src/el-file.c b/src/el-file.c
index 2ac3180..afa2560 100644
--- a/src/el-file.c
+++ b/src/el-file.c
@@ -65,44 +65,11 @@
 
 
 /* ==========================================================================
-    checks if we can (or should) write to a file
-   ========================================================================== */
-
-
-static int el_file_is_writeable
-(
-    struct el_options  *options,  /* file options */
-    size_t              slen      /* length of string caller wants to print */
-)
-{
-    if (options->file == NULL)
-    {
-        /*
-         * well, it's hard to write to a file if it is not opened
-         */
-
-        return 0;
-    }
-
-    if (options->fpos + slen > options->frotate_size)
-    {
-        /*
-         * writing to file, would overflow it (according to frotate_size
-         * set by user), so write should no be allowed.
-         */
-
-        return 0;
-    }
-
-    return 1;
-}
-
-
-/* ==========================================================================
     function rotates file, meaning if currently opened file has  suffix  .3,
     function will close that file and will open file  with  suffix  .4.   If
     creating  new  suffix  is  impossible  (we  reached  frotate_number   of
-    suffixed) function will rename files, and create new file with suffix .0
+    suffixed) function will remove oldest log file  and  new  file  will  be
+    created
    ========================================================================== */
 
 
@@ -230,6 +197,12 @@ int el_file_open
 {
     if (options->file)
     {
+        off_t fsize;  /* size of the opened file we close */
+        /*~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~*/
+
+
+        fsize = ftell(options->file);
+
         /*
          * to prevent any memory leak in  case  of  double  open,  we  first
          * close already opened file Such situation may happen when  library
@@ -237,6 +210,17 @@ int el_file_open
          */
 
         fclose(options->file);
+
+        if (fsize == 0)
+        {
+            /*
+             * file is empty, so we get rid of it, as it was probably opened
+             * by mistake
+             */
+
+            remove(options->fname);
+        }
+
         options->file = NULL;
     }
 
@@ -356,25 +340,49 @@ int el_file_puts
     /*~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~*/
 
 
-    sl = strlen(s);
-
-    if (options->frotate_number && el_file_is_writeable(options, sl) == 0)
+    if (options->file == NULL)
     {
         /*
-         * we get here only when frotate is enabled, and writing to  current
-         * file would result in exceding frotate_size of file. In suche case
-         * we rotate the file by closing the old one and opening  new  file,
-         * and if we already filled  frotate_number  files,  we  remove  the
-         * oldest one, unless frotate_number is -1, then we  rotate  without
-         * deleting anything.
+         * file has not been opened, prevent segfault
          */
 
-        if (el_file_rotate(options) != 0)
+        errno = EBADF;
+        return -1;
+    }
+
+    sl = strlen(s);
+
+    if (options->frotate_number)
+    {
+        if (options->fpos + sl > options->frotate_size)
+        {
+            /*
+             * we get here only when frotate  is  enabled,  and  writing  to
+             * current file would result in exceding frotate_size  of  file.
+             * In such case we rotate the file by closing the  old  one  and
+             * opening new file, and if  we  already  filled  frotate_number
+             * files,  we  remove  the oldest one.
+             */
+
+            if (el_file_rotate(options) != 0)
+            {
+                return -1;
+            }
+        }
+
+        if (sl > options->frotate_size)
         {
-            return -1;
+            /*
+             * we can't fit message even in an empty file, in such  case  we
+             * need to truncate log, so we don't  create  file  bigger  than
+             * configured frotate_size
+             */
+
+            sl = options->frotate_size;
         }
     }
 
+
     if (fwrite(s, sl, 1, options->file) != 1)
     {
         return -1;
diff --git a/src/el-options.c b/src/el-options.c
index 0ade6d7..404da17 100644
--- a/src/el-options.c
+++ b/src/el-options.c
@@ -203,14 +203,36 @@ static int el_vooption
 
     case EL_OPT_FNAME:
         value_str = va_arg(ap, const char *);
+        VALID(EINVAL, value_str);
         options->fname = value_str;
         return el_file_open(options);
 
     case EL_OPT_FROTATE_NUMBER:
+    {
+        int previous_frotate; /* previous value of frotate number */
+        /*~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~*/
+
+
         value_int = va_arg(ap, int);
         VALID(EINVAL, value_int >= 0);
+        previous_frotate = options->frotate_number;
         options->frotate_number = value_int;
+
+        if (previous_frotate == 0 && options->file)
+        {
+            /*
+             * user turned on file rotation  when  file  is  already  opened
+             * without rotation.  To prevent weird situations and even  data
+             * loss, we reopen file as opening with log rotation  is  a  bit
+             * different.  el_file_open  function  will  close  file  before
+             * reopening
+             */
+
+            return el_file_open(options);
+        }
+
         return 0;
+    }
 
     case EL_OPT_FROTATE_SIZE:
         value_long = va_arg(ap, long);
@@ -299,10 +321,11 @@ int el_cleanup
 
 
 /* ==========================================================================
-    cleans up whatever has been initialized/reserver by el_cleanup
+    cleans up  whatever  has  been  initialized/reserved  by  el_option  and
+    el_init calls
 
     errno
-            EINVAL      options is invlaid (null)
+            EINVAL      options is invalid (null)
    ========================================================================== */
 
 
diff --git a/src/el-perror.c b/src/el-perror.c
index c5a5d86..b6c6171 100644
--- a/src/el-perror.c
+++ b/src/el-perror.c
@@ -33,6 +33,63 @@
 
 
 /* ==========================================================================
+                                   _                __
+                     ____   _____ (_)_   __ ____ _ / /_ ___
+                    / __ \ / ___// /| | / // __ `// __// _ \
+                   / /_/ // /   / / | |/ // /_/ // /_ /  __/
+                  / .___//_/   /_/  |___/ \__,_/ \__/ \___/
+                 /_/
+               ____                     __   _
+              / __/__  __ ____   _____ / /_ (_)____   ____   _____
+             / /_ / / / // __ \ / ___// __// // __ \ / __ \ / ___/
+            / __// /_/ // / / // /__ / /_ / // /_/ // / / /(__  )
+           /_/   \__,_//_/ /_/ \___/ \__//_/ \____//_/ /_//____/
+
+   ========================================================================== */
+
+
+/* ==========================================================================
+    calls el_print with 'fmt' and '...' parameters, but  additionaly  prints
+    information about errno.  Functionaly it is similar to  perror  function
+   ========================================================================== */
+
+
+static int el_ovperror
+(
+    const char         *file,     /* file name where log is printed */
+    size_t              num,      /* line number where log is printed */
+    enum el_level       level,    /* log level to print message with */
+    struct el_options  *options,  /* options defining printing style */
+    const char         *fmt,      /* message format (see printf (3)) */
+    va_list             ap        /* additional parameters for fmt */
+)
+{
+    int                 rc;       /* return code from el_print() */
+    unsigned long       e;        /* errno from upper layer */
+    /*~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~*/
+
+
+    e = errno;
+    rc = 0;
+
+    if (fmt)
+    {
+        /*
+         * we print formatted message only when it is supplied by the user,
+         * otherwise only errno message will be printed
+         */
+
+        rc |= el_ovprint(file, num, level, options, fmt, ap);
+    }
+
+    rc |= el_oprint(file, num, level, options,
+        "errno num: %lu, strerror: %s", e, strerror(e));
+
+    return rc;
+}
+
+
+/* ==========================================================================
                                         __     __ _
                          ____   __  __ / /_   / /(_)_____
                         / __ \ / / / // __ \ / // // ___/
@@ -56,26 +113,22 @@
 
 int el_perror
 (
-    const char    *file,                 /* file name where log is printed */
-    size_t         num,                  /* line number where log is printed */
-    enum el_level  level,                /* log level to print message with */
-    const char    *fmt,                  /* message format (see printf (3)) */
-                   ...                   /* additional parameters for fmt */
+    const char    *file,   /* file name where log is printed */
+    size_t         num,    /* line number where log is printed */
+    enum el_level  level,  /* log level to print message with */
+    const char    *fmt,    /* message format (see printf (3)) */
+                   ...     /* additional parameters for fmt */
 )
 {
-    va_list        ap;                   /* arguments '...' for 'fmt' */
-    int            rc;                   /* return code from el_print() */
-    unsigned long  e;                    /* errno from upper layer */
+    int            rc;     /* return code from el_operror() */
     /*~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~*/
 
 
-    e = errno;
-
     va_start(ap, fmt);
-    rc  = el_ovprint(file, num, level, &g_options, fmt, ap);
-    rc |= el_oprint(file, num, level, &g_options,
-        "errno num: %lu, strerror: %s", e, strerror(e));
+    rc = el_ovperror(file, num, level, &g_options, fmt, ap);
     va_end(ap);
+
+    return rc;
 }
 
 
@@ -94,17 +147,13 @@ int el_operror
                        ...        /* additional parameters for fmt */
 )
 {
-    va_list            ap;        /* arguments '...' for 'fmt' */
-    int                rc;        /* return code from el_print() */
-    unsigned long      e;         /* errno from upper layer */
+    int                rc;        /* return code from el_operror() */
     /*~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~*/
 
 
-    e = errno;
-
     va_start(ap, fmt);
-    rc  = el_ovprint(file, num, level, options, fmt, ap);
-    rc |= el_oprint(file, num, level, options,
-        "errno num: %lu, strerror: %s", e, strerror(e));
+    rc = el_ovperror(file, num, level, options, fmt, ap);
     va_end(ap);
+
+    return rc;
 }
diff --git a/src/el-print.c b/src/el-print.c
index 3223ebc..559a1e7 100644
--- a/src/el-print.c
+++ b/src/el-print.c
@@ -600,7 +600,10 @@ int el_ovprint
     buf[w++] = '\n';
     buf[w++] = '\0';
 
-    el_oputs(options, buf);
+    if (el_oputs(options, buf) != 0)
+    {
+        return -1;
+    }
 
     if (e)
     {