[PATCH/WIP 1/8] wrapper: implement xopen()
From: Paul Tan <hidden>
Date: 2016-06-15 23:05:01
Subsystem:
the rest · Maintainer:
Linus Torvalds
A common usage pattern of open() is to check if it was successful, and
die() if it was not:
int fd = open(path, O_WRONLY | O_CREAT, 0777);
if (fd < 0)
die_errno(_("Could not open '%s' for writing."), path);
Implement a wrapper function xopen() that does the above so that we can
save a few lines of code, and make the die() messages consistent.
Signed-off-by: Paul Tan <redacted>
---
git-compat-util.h | 1 +
wrapper.c | 18 ++++++++++++++++++
2 files changed, 19 insertions(+)
diff --git a/git-compat-util.h b/git-compat-util.h
index 17584ad..9745962 100644
--- a/git-compat-util.h
+++ b/git-compat-util.h@@ -718,6 +718,7 @@ extern char *xstrndup(const char *str, size_t len); extern void *xrealloc(void *ptr, size_t size); extern void *xcalloc(size_t nmemb, size_t size); extern void *xmmap(void *start, size_t length, int prot, int flags, int fd, off_t offset); +extern int xopen(const char *path, int flags, mode_t mode); 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);
diff --git a/wrapper.c b/wrapper.c
index c1a663f..971665a 100644
--- a/wrapper.c
+++ b/wrapper.c@@ -189,6 +189,24 @@ void *xcalloc(size_t nmemb, size_t size) # endif #endif +/** + * xopen() is the same as open(), but it die()s if the open() fails. + */ +int xopen(const char *path, int flags, mode_t mode) +{ + int fd; + + assert(path); + fd = open(path, flags, mode); + if (fd < 0) { + if ((flags & O_WRONLY) || (flags & O_RDWR)) + die_errno(_("could not open '%s' for writing"), path); + else + die_errno(_("could not open '%s' for reading"), path); + } + return fd; +} + /* * xread() is the same a read(), but it automatically restarts read() * operations with a recoverable error (EAGAIN and EINTR). xread()
--
2.1.4