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![Yiannis Marangos](/assets/img/avatar_default.png)
It is a common mistake to call read(2)/pread(2) and forget to anticipate that they may return error with EAGAIN/EINTR when the system call is interrupted. We have xread() helper to relieve callers of read(2) from having to worry about it; add xpread() helper to do the same for pread(2). Update the caller in the builtin/index-pack.c and the mmap emulation in compat/. Signed-off-by: Yiannis Marangos <yiannis.marangos@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
41 lines
692 B
C
41 lines
692 B
C
#include "../git-compat-util.h"
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void *git_mmap(void *start, size_t length, int prot, int flags, int fd, off_t offset)
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{
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size_t n = 0;
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if (start != NULL || !(flags & MAP_PRIVATE))
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die("Invalid usage of mmap when built with NO_MMAP");
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start = xmalloc(length);
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if (start == NULL) {
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errno = ENOMEM;
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return MAP_FAILED;
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}
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while (n < length) {
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ssize_t count = xpread(fd, (char *)start + n, length - n, offset + n);
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if (count == 0) {
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memset((char *)start+n, 0, length-n);
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break;
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}
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if (count < 0) {
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free(start);
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errno = EACCES;
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return MAP_FAILED;
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}
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n += count;
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}
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return start;
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}
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int git_munmap(void *start, size_t length)
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{
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free(start);
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return 0;
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}
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