- loadmodule now reports proper errors when the actual file can't be found, instead of blaming

it on the temp file, reported in #3015.
(aquanight backport)

Changes

@@ -1355,3 +1355,5 @@
 - Fixed set::allowed-nickchars causing a segfault for some unknown charsets, reported
   by avb (#0003069).
 - Cutoff webtv whois at MAXTARGETS (#0003004).
+- loadmodule now reports proper errors when the actual file can't be found, instead of blaming
+  it on the temp file, reported in #3015.

src/modules.c

@@ -331,14 +331,25 @@ char  *Module_Create(char *path_)
 		strcpy(path, "./");
 		strcat(path, path_);
 	}
+
+	if (!file_exists(path))
+	{
+		snprintf(errorbuf, sizeof(errorbuf), "Cannot open module file: %s", strerror(errno));
+		return errorbuf;
+	}
 #ifdef __OpenBSD__
 	/* For OpenBSD, do not do a hardlinkink attempt first because it checks inode
 	 * numbers to see if a certain module is already loaded. -- Syzop
 	 */
-	unreal_copyfileex(path, tmppath, 0);
+	ret = unreal_copyfileex(path, tmppath, 0);
 #else
-	unreal_copyfileex(path, tmppath, 1);
+	ret = unreal_copyfileex(path, tmppath, 1);
 #endif
+	if (!ret)
+	{
+		snprintf(errorbuf, sizeof(errorbuf), "Failed to copy module file.");
+		return errorbuf;
+	}
 	if ((Mod = irc_dlopen(tmppath, RTLD_NOW)))
 	{
 		/* We have engaged the borg cube. Scan for lifesigns. */

src/support.c

@@ -1675,6 +1675,17 @@ void	*MyMallocEx(size_t size)
 	return (p);
 }
 
+int file_exists(char* file)
+{
+	FILE *fd;
+	fd = fopen(file, "r");
+	if (!fd)
+	{
+		return 0;
+	}
+	return 1;
+}
+
 /* Returns a unique filename in the specified directory
  * using the specified suffix. The returned value will
  * be of the form <dir>/<random-hex>.<suffix>
@@ -1766,7 +1777,10 @@ int unreal_copyfile(char *src, char *dest)
 #endif
 
 	if (srcfd < 0)
+	{
+		config_error("Unable to open file '%s': %s", src, strerror(errno));
 		return 0;
+	}
 
 #ifndef _WIN32
 	destfd  = open(dest, O_WRONLY|O_CREAT, DEFAULT_PERMISSIONS);
@@ -1814,7 +1828,7 @@ int unreal_copyfileex(char *src, char *dest, int tryhardlink)
 #ifndef _WIN32
 	/* Try a hardlink first... */
 	if (tryhardlink && !link(src, dest))
-		return 0; /* success */
+		return 1; /* success */
 #endif
 	return unreal_copyfile(src, dest);
 }