makedep: Copy the makefile to append dependencies instead of truncating in place.
diff --git a/tools/makedep.c b/tools/makedep.c
index 2571359..7941ea0 100644
--- a/tools/makedep.c
+++ b/tools/makedep.c
@@ -866,6 +866,33 @@
/*******************************************************************
+ * create_temp_file
+ */
+static FILE *create_temp_file( char **tmp_name )
+{
+ char *name = xmalloc( strlen(OutputFileName) + 13 );
+ unsigned int i, id = getpid();
+ int fd;
+ FILE *ret = NULL;
+
+ for (i = 0; i < 100; i++)
+ {
+ sprintf( name, "%s.tmp%08x", OutputFileName, id );
+ if ((fd = open( name, O_RDWR | O_CREAT | O_EXCL, 0600 )) != -1)
+ {
+ ret = fdopen( fd, "w" );
+ break;
+ }
+ if (errno != EEXIST) break;
+ id += 7777;
+ }
+ if (!ret) fatal_error( "failed to create output file for '%s'\n", OutputFileName );
+ *tmp_name = name;
+ return ret;
+}
+
+
+/*******************************************************************
* output_dependencies
*/
static void output_dependencies(void)
@@ -873,19 +900,23 @@
INCL_FILE *pFile;
int i, column;
FILE *file = NULL;
- char *buffer;
+ char *tmp_name = NULL;
- if (Separator && ((file = fopen( OutputFileName, "r+" ))))
+ if (Separator && ((file = fopen( OutputFileName, "r" ))))
{
- while ((buffer = get_line( file )))
+ char buffer[1024];
+ FILE *tmp_file = create_temp_file( &tmp_name );
+
+ while (fgets( buffer, sizeof(buffer), file ))
{
- if (strncmp( buffer, Separator, strlen(Separator) )) continue;
- ftruncate( fileno(file), ftell(file) );
- fseek( file, 0L, SEEK_END );
- break;
+ if (fwrite( buffer, 1, strlen(buffer), tmp_file ) != strlen(buffer))
+ fatal_error( "error writing to %s\n", tmp_name );
+ if (!strncmp( buffer, Separator, strlen(Separator) )) break;
}
+ fclose( file );
+ file = tmp_file;
}
- if (!file)
+ else
{
if (!(file = fopen( OutputFileName, Separator ? "a" : "w" )))
{
@@ -902,7 +933,17 @@
pFile, &column );
fprintf( file, "\n" );
}
- fclose(file);
+ fclose( file );
+
+ if (tmp_name)
+ {
+ if (rename( tmp_name, OutputFileName ) == -1)
+ {
+ unlink( tmp_name );
+ fatal_error( "failed to rename output file to '%s'\n", OutputFileName );
+ }
+ free( tmp_name );
+ }
}
