[[ Bug 16745 ]] Fix $_POST_RAW on Windows Server

montegoulding · montegoulding · commit 7f49088de2f9 · 2021-04-29T13:12:42.000+10:00
This patch fixes an issue where `$_POST_RAW` was not set if posted data
was too large to be buffered. The issue was caused by:

* When a file was created for caching the post data it was using `OpenFd`
which only supports the stdio handles on Windows.
* When reading from the cache we need to iterate until the read either
fails or completes the required read length.
diff --git a/docs/notes/bugfix-16745.md b/docs/notes/bugfix-16745.md
@@ -0,0 +1 @@
+# An issue causing `$_POST_RAW` on Windows to not be set for large uploads has been fixed.
diff --git a/engine/src/srvcgi.cpp b/engine/src/srvcgi.cpp
@@ -993,10 +993,16 @@ static bool cgi_compute_post_raw_var(void *p_context, MCVariable *p_var)
 		t_length = atoi(MCStringGetCString(*t_content_length));
 		
 		uint32_t t_read = 0;
+		uint32_t t_offset = 0;
 		
 		char *t_data;
 		t_data = new (nothrow) char[t_length];
-		t_success = t_stdin->Read(t_data, t_length, t_read) && t_length == t_read;
+		while (t_stdin->Read(t_data, t_length - t_offset, t_read) && t_offset < t_length)
+		{
+			/* read until length satisfied */
+			t_offset += t_read;
+		}
+		t_success = t_length == t_offset;
 
 		// Store the raw POST data
 		if (t_success)
diff --git a/engine/src/srvwindows.cpp b/engine/src/srvwindows.cpp
@@ -1241,28 +1241,18 @@ bool MCS_get_temporary_folder(MCStringRef &r_temp_folder)
 
 bool MCS_create_temporary_file(MCStringRef p_path_string, MCStringRef p_prefix_string, IO_handle &r_file, MCStringRef &r_name_string)
 {
-	const char *t_path = MCStringGetCString(p_path_string);
-	const char *t_prefix = MCStringGetCString(p_prefix_string);
-	char *t_name = (char*)MCStringGetCString(r_name_string);
-
 	bool t_success = true;
-	bool t_have_file = false;
 	
-	char *t_temp_file = NULL;
 	GUID t_guid;
 	WCHAR *t_guid_utf16 = NULL;
 	
-	HANDLE t_temp_handle = NULL;
+	IO_handle t_temp_handle = NULL;
 	
-	while (t_success && !t_have_file)
+	MCAutoStringRef t_temp_file;
+	while (t_success && t_temp_handle == NULL)
 	{
 		CoCreateGuid(&t_guid);
 		
-		if (t_temp_file != NULL)
-		{
-			MCCStringFree(t_temp_file);
-			t_temp_file = NULL;
-		}
 		if (t_guid_utf16 != NULL)
 		{
 			CoTaskMemFree(t_guid_utf16);
@@ -1277,28 +1267,22 @@ bool MCS_create_temporary_file(MCStringRef p_path_string, MCStringRef p_prefix_s
 			for (i = 0; t_guid_utf16[i] != '\0'; i++)
 				t_guid_string[i] = t_guid_utf16[i] & 0xFF;
 			t_guid_string[i] = '\0';
-			t_success = MCCStringFormat(t_temp_file, "%s/%s%s", t_path, t_prefix, t_guid_string);
+			t_success = MCStringFormat(&t_temp_file, "%@/%@%s", p_path_string, p_prefix_string, t_guid_string);
 		}
 		
 		if (t_success)
 		{
-			t_temp_handle = CreateFileA(t_temp_file, GENERIC_READ | GENERIC_WRITE, 0, NULL, CREATE_NEW, FILE_ATTRIBUTE_NORMAL, NULL);
-			if (t_temp_handle != INVALID_HANDLE_VALUE)
-				t_have_file = true;
-			else
+			t_temp_handle = MCsystem->OpenFile(*t_temp_file, (intenum_t)kMCOpenFileModeCreate, false);
+			if (t_temp_handle == NULL)
 				t_success = GetLastError() == ERROR_FILE_EXISTS;
 		}
 	}
 	
 	if (t_success)
 	{
-		r_file = MCsystem -> OpenFd(_open_osfhandle((intptr_t)t_temp_handle, _O_RDWR), kMCOpenFileModeCreate);
-		t_name = t_temp_file;
-		/* UNCHECKED */ MCStringCreateWithCString(t_name, r_name_string);
-
+		r_file = t_temp_handle;
+		r_name_string = t_temp_file.Take();
 	}
-	else
-		MCCStringFree(t_temp_file);
 	
 	CoTaskMemFree(t_guid_utf16);
 	return t_success;

Original file line number	Diff line number	Diff line change
`@@ -0,0 +1 @@`
	`1`	+# An issue causing `$_POST_RAW` on Windows to not be set for large uploads has been fixed.