shithub: rgbds

Info  •  Files  •  Log  •  Branches

Make RGBASM overwrite output files atomically
Fixes rednex/#446.
I am not sure this is the best (in cases where the target directory
is not writable but the target file is), but maybe this can be
toggled via a flag, for example.

--- a/src/asm/output.c

+++ b/src/asm/output.c

@@ -16,6 +16,8 @@

 #include <stdint.h>

 #include <stdlib.h>

 #include <string.h>

+#include <unistd.h>

+#include <libgen.h>

 #include "asm/asm.h"

 #include "asm/charmap.h"

@@ -532,13 +534,25 @@

  */

 void out_WriteObject(void)

 {

+	/* Write to a temporary file in the target's folder */

+	char *objectNameCopy = strdup(tzObjectname);

+	char const *dirPath = dirname(objectNameCopy);

+	char tmpFileName[strlen(dirPath) + 1 + 16 + 1];

+

+	sprintf(tmpFileName, "%s/rgbasm_tmpXXXXXX", dirPath);

+	free(objectNameCopy);

+	int fd = mkstemp(tmpFileName);

+

 	FILE *f;

 	struct PatchSymbol *pSym;

 	struct Section *pSect;

+	if (fd == -1)

+		err(1, "Couldn't create temporary file");

+

 	addexports();

-	f = fopen(tzObjectname, "wb");

+	f = fdopen(fd, "wb");

 	if (f == NULL)

 		fatalerror("Couldn't write file '%s'\n", tzObjectname);

@@ -560,6 +574,11 @@

 	}

 	fclose(f);

+	close(fd);

+

+	if (rename(tmpFileName, tzObjectname) != 0)

+		err(1, "Couldn't create object file (temp file kept as %s)",

+		    tmpFileName);

 }

 /*