wrapper: implement xfopen()
A common usage pattern of fopen() is to check if it succeeded, and die()
if it failed:
FILE *fp = fopen(path, "w");
if (!fp)
die_errno(_("could not open '%s' for writing"), path);
Implement a wrapper function xfopen() for the above, so that we can save
a few lines of code and make the die() messages consistent.
Helped-by: Jeff King <peff@peff.net>
Helped-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Helped-by: Junio C Hamano <gitster@pobox.com>
Signed-off-by: Paul Tan <pyokagan@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
diff --git a/git-compat-util.h b/git-compat-util.h
index e168dfd..392da79 100644
--- a/git-compat-util.h
+++ b/git-compat-util.h
@@ -722,6 +722,7 @@
extern ssize_t xwrite(int fd, const void *buf, size_t len);
extern ssize_t xpread(int fd, void *buf, size_t len, off_t offset);
extern int xdup(int fd);
+extern FILE *xfopen(const char *path, const char *mode);
extern FILE *xfdopen(int fd, const char *mode);
extern int xmkstemp(char *template);
extern int xmkstemp_mode(char *template, int mode);
diff --git a/wrapper.c b/wrapper.c
index 0a4502d..e451463 100644
--- a/wrapper.c
+++ b/wrapper.c
@@ -346,6 +346,27 @@
return ret;
}
+/**
+ * xfopen() is the same as fopen(), but it die()s if the fopen() fails.
+ */
+FILE *xfopen(const char *path, const char *mode)
+{
+ for (;;) {
+ FILE *fp = fopen(path, mode);
+ if (fp)
+ return fp;
+ if (errno == EINTR)
+ continue;
+
+ if (*mode && mode[1] == '+')
+ die_errno(_("could not open '%s' for reading and writing"), path);
+ else if (*mode == 'w' || *mode == 'a')
+ die_errno(_("could not open '%s' for writing"), path);
+ else
+ die_errno(_("could not open '%s' for reading"), path);
+ }
+}
+
FILE *xfdopen(int fd, const char *mode)
{
FILE *stream = fdopen(fd, mode);
