From 260eec292736388831958637eccdcf1a8f00e14d Mon Sep 17 00:00:00 2001 From: Paul Tan Date: Tue, 4 Aug 2015 21:51:23 +0800 Subject: [PATCH] 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 Helped-by: Johannes Schindelin Helped-by: Junio C Hamano Signed-off-by: Paul Tan Signed-off-by: Junio C Hamano --- git-compat-util.h | 1 + wrapper.c | 21 +++++++++++++++++++++ 2 files changed, 22 insertions(+) diff --git a/git-compat-util.h b/git-compat-util.h index e168dfd68b..392da79029 100644 --- a/git-compat-util.h +++ b/git-compat-util.h @@ -722,6 +722,7 @@ extern ssize_t xread(int fd, void *buf, size_t len); 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 0a4502d232..e451463431 100644 --- a/wrapper.c +++ b/wrapper.c @@ -346,6 +346,27 @@ int xdup(int fd) 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);