cleaned up unixmbox.c and mailbox.c

added optional argument to from.c
added items to TODO
added Makefile for from.c in examples

+Sean 'Shaleh' Perry <shaleh@debian.org>  Fri,  8 Oct 1999 01:08:42 -0700
+
+  * fixed the "if empty mailbox, return not implemented"
+    NB: seems there was a large assumption being made:
+        if unixmbox_open() failed, it was because it was not mbox
+    this was wrong for many reasons, so on actual "not mbox", return EBADMSG.
+    Prolly want to come up with a better error, but this works for now
+  * more cleaning in the mailbox code
+    a) added stat() call -- we can bomb earlier, plus detect if passed object
+       is a directory or file
+    b) unixmbox_close() free()'s mbox.  This will hamper the use when we add
+       support for more mailboxes later.  Need to find a solution.  Perhaps
+       a unixmbox_free() call.
+       There was also a small leak there -- mbox->name was being left.
+    c) To aid checking in unixbox_open(), added checks around fgets call.
+       Now properly detects EOF, errors, etc.  This was a large cause of the
+	   spurious "not implemented" bug.
+    d) all of unixmbox_open()'s function calls should now be checked
+	   NB: need to do the same for rest of file
+
 Sean 'Shaleh' Perry <shaleh@debian.org>  Thu,  7 Oct 1999 22:33:24 -0700
 
   * removed spurious code in from.c

++ --> fixed/done
+- --> pending
+= --> on hold
+* --> in progress
+
 - autogen.sh (libtool) complains about libmailbox.la in noinst
 
-- libmailbox has a nasty bug -- if the mailbox is empty, the library has no idea
++ libmailbox has a nasty bug -- if the mailbox is empty, the library has no idea
   what to do
   
+- libmailbox needs an interface to set flags for each message
+
+- libmailbox needs an interface to set and create values in the header
+
 - crypt is linked even if pam was detected, it should be one or the other
 
 - test daemon code

+CFLAGS = -Wall -pedantic -g
+INCLUDES = -I../libmailbox
+LIBS = ../libmailbox/.libs/libmailbox.al
+
+from: from.c $(LIBS)
+	gcc $(CFLAGS) $(INCLUDES) -o from from.c $(LIBS)
+
+clean:
+	rm -f from

@@ -22,23 +22,32 @@ int main(int argc, char *argv[]) {
         fprintf(stderr, "who am I?\n");
         exit(-1);
       }
+	if (!strcmp(user, "root") && argc == 2)
+		user = argv[1];
+	else if (argc > 2)
+      {
+        fprintf(stderr,
+				"Usage: from [username] (argument valid when ran as root)\n");
+		exit(-1);
+      }
+
 	snprintf (mailpath, 256, "%s/%s", _PATH_MAILDIR, user);
 	mail = mbox_open(mailpath);
 	if( mail == NULL ) {
-		perror("mbox_open: ");
+		perror("mbox_open");
 		exit(-1);
 	}
 	for(i = 0; i < mail->messages; ++i) {
 		from = mbox_header_line(mail, i, "From");
 		if (from == NULL)
           {
-            perror("mbox_header_line: ");
+            perror("mbox_header_line");
             exit(-1);
           }
 		date = mbox_header_line(mail, i, "Date");
 		if (date == NULL)
           {
-            perror("mbox_header_line: ");
+            perror("mbox_header_line");
             exit(-1);
           }
 		printf("%s %s\n", from, date);

@@ -26,6 +26,9 @@
 #include <errno.h>
 #endif
 
+#include <sys/stat.h>
+#include <unistd.h>
+
 int _mbox_dummy1 (mailbox * mbox);
 int _mbox_dummy2 (mailbox * mbox, unsigned int num);
 int _mbox_dummy3 (mailbox * mbox, char *c);
@@ -35,6 +38,7 @@ mailbox *
 mbox_open (const char *name)
 {
   mailbox *mbox;
+  struct stat st;
 
   if ( name == NULL )
     {
@@ -57,6 +61,14 @@ mbox_open (const char *name)
       free (mbox);
       return NULL;
     }
+  /* check if we can look at file, prep for checks later in function */
+  if (stat (mbox->name, &st) == -1)
+    {
+      free (mbox->name);
+	  free (mbox);
+	  return NULL; /* errno set by stat() */
+    }
+
   mbox->messages = 0;
   mbox->num_deleted = 0;
   mbox->sizes = NULL;
@@ -71,27 +83,38 @@ mbox_open (const char *name)
   mbox->_get_body = _mbox_dummy4;
   mbox->_get_header = _mbox_dummy4;
 
-  if (unixmbox_open (mbox) == 0)
-    return mbox;
-  else
+  if (S_ISDIR (st.st_mode))
     {
-      /*
-       * Check errno to find out why it failed, if it's simply not a
-       * unix mbox format message, then try other mailbox types,
-       * otherwise, leave errno set and return NULL
+      /* for example...
+         if (maildir_open (mbox, name) == 1)
+           return mbox;
+         else if (errno != 0)
+           return NULL;
+         else
+           errno = 0;
        */
+      errno = ENOSYS;
     }
+  else if (S_ISREG (st.st_mode))
+    {
+      if (unixmbox_open (mbox) == 0)
+        return mbox;
+      else
+        {
+          /*
+           * Check errno to find out why it failed, if it's simply not a
+           * unix mbox format message, then try other mailbox types,
+           * otherwise, leave errno set and return NULL
+           */
+          if (errno == EBADMSG)
+            errno = ENOSYS; /* no other mailboxes supported right now */
+        }
+    }
+  else
+    errno = EINVAL; /* neither directory nor file, so bomb */
 
-  /* for example...
-     if (maildir_open (mbox, name) == 1)
-       return mbox;
-     else if (errno != 0)
-       return NULL;
-     else
-       errno = 0;
-   */
-
-  errno = ENOSYS;
+  free (mbox->name);
+  free (mbox);
   return NULL;
 }
 

@@ -38,10 +38,8 @@
 #define mbox_lock(m,n)		m->_lock(m,n)
 
 /* Lock settings */
-/*
- * define this way so that it is opaque and can later become a struct w/o
+/* define this way so that it is opaque and can later become a struct w/o
  * people noticing (-:
- *
  */
 enum _mailbox_lock_t {MO_ULOCK, MO_RLOCK, MO_WLOCK}; /* new type */
 typedef enum _mailbox_lock_t mailbox_lock_t;

@@ -64,12 +64,18 @@ unixmbox_open (mailbox * mbox)
       return -1;
     }
 
-  fgets (buf, 80, data->file);
+  if (fgets (buf, 80, data->file) == NULL)
+    {
+      if (feof(data->file))
+        goto END; /* empty file, no messages */
+	  unixmbox_close (mbox);
+	  return -1;
+    }
   if (strncmp (buf, "From ", 5))
     {
       /* This is NOT an mbox file */
       unixmbox_close (mbox);
-      errno = 0;
+      errno = EBADMSG; /* use this to signify wrong mbox type */
       return -1;
     }
 
@@ -79,7 +85,13 @@ unixmbox_open (mailbox * mbox)
 	{
 	  /* Beginning of a header */
 	  while (strchr (buf, '\n') == NULL)
-	    fgets (buf, 80, data->file); /* eat the From line */
+	    if (fgets (buf, 80, data->file) == NULL) /* eat the From line */
+          {
+            if (feof (data->file))
+              errno = EIO; /* corrupted mailbox? */
+            unixmbox_close (mbox);
+            return -1;
+          }
 
 	  mbox->messages++;
 
@@ -117,6 +129,13 @@ unixmbox_open (mailbox * mbox)
     }
   while (fgets (buf, 80, data->file));
 
+  if (!feof (data->file)) /* stopped due to error, not EOF */
+    {
+      unixmbox_close (mbox);
+      return -1; /* errno is set */
+    }
+
+END:
   mbox->_close = unixmbox_close;
   mbox->_delete = unixmbox_delete;
   mbox->_undelete = unixmbox_undelete;
@@ -149,7 +168,6 @@ unixmbox_close (mailbox * mbox)
   free (data->messages);
   free (mbox->sizes);
   free (data);
-  free (mbox);
   return 0;
 }