libgit2/src/posix.c
Carlos Martín Nieto f7310540ae indexer: use mmap for writing
Some OSs cannot keep their ideas about file content straight when mixing
standard IO with file mapping. As we use mmap for reading from the
packfile, let's make writing to the pack file use mmap.
2014-05-17 01:39:43 +02:00

250 lines
4.6 KiB
C

/*
* Copyright (C) the libgit2 contributors. All rights reserved.
*
* This file is part of libgit2, distributed under the GNU GPL v2 with
* a Linking Exception. For full terms see the included COPYING file.
*/
#include "common.h"
#include "posix.h"
#include "path.h"
#include <stdio.h>
#include <ctype.h>
#ifndef GIT_WIN32
#ifdef NO_ADDRINFO
int p_getaddrinfo(
const char *host,
const char *port,
struct addrinfo *hints,
struct addrinfo **info)
{
struct addrinfo *ainfo, *ai;
int p = 0;
GIT_UNUSED(hints);
if ((ainfo = malloc(sizeof(struct addrinfo))) == NULL)
return -1;
if ((ainfo->ai_hostent = gethostbyname(host)) == NULL) {
free(ainfo);
return -2;
}
ainfo->ai_servent = getservbyname(port, 0);
if (ainfo->ai_servent)
ainfo->ai_port = ainfo->ai_servent->s_port;
else
ainfo->ai_port = atol(port);
memcpy(&ainfo->ai_addr_in.sin_addr,
ainfo->ai_hostent->h_addr_list[0],
ainfo->ai_hostent->h_length);
ainfo->ai_protocol = 0;
ainfo->ai_socktype = hints->ai_socktype;
ainfo->ai_family = ainfo->ai_hostent->h_addrtype;
ainfo->ai_addr_in.sin_family = ainfo->ai_family;
ainfo->ai_addr_in.sin_port = ainfo->ai_port;
ainfo->ai_addr = (struct addrinfo *)&ainfo->ai_addr_in;
ainfo->ai_addrlen = sizeof(struct sockaddr_in);
*info = ainfo;
if (ainfo->ai_hostent->h_addr_list[1] == NULL) {
ainfo->ai_next = NULL;
return 0;
}
ai = ainfo;
for (p = 1; ainfo->ai_hostent->h_addr_list[p] != NULL; p++) {
ai->ai_next = malloc(sizeof(struct addrinfo));
memcpy(&ai->ai_next, ainfo, sizeof(struct addrinfo));
memcpy(&ai->ai_next->ai_addr_in.sin_addr,
ainfo->ai_hostent->h_addr_list[p],
ainfo->ai_hostent->h_length);
ai->ai_next->ai_addr = (struct addrinfo *)&ai->ai_next->ai_addr_in;
ai = ai->ai_next;
}
ai->ai_next = NULL;
return 0;
}
void p_freeaddrinfo(struct addrinfo *info)
{
struct addrinfo *p, *next;
p = info;
while(p != NULL) {
next = p->ai_next;
free(p);
p = next;
}
}
const char *p_gai_strerror(int ret)
{
switch(ret) {
case -1: return "Out of memory"; break;
case -2: return "Address lookup failed"; break;
default: return "Unknown error"; break;
}
}
#endif /* NO_ADDRINFO */
int p_open(const char *path, volatile int flags, ...)
{
mode_t mode = 0;
if (flags & O_CREAT) {
va_list arg_list;
va_start(arg_list, flags);
mode = (mode_t)va_arg(arg_list, int);
va_end(arg_list);
}
return open(path, flags | O_BINARY | O_CLOEXEC, mode);
}
int p_creat(const char *path, mode_t mode)
{
return open(path, O_WRONLY | O_CREAT | O_TRUNC | O_BINARY | O_CLOEXEC, mode);
}
int p_getcwd(char *buffer_out, size_t size)
{
char *cwd_buffer;
assert(buffer_out && size > 0);
cwd_buffer = getcwd(buffer_out, size);
if (cwd_buffer == NULL)
return -1;
git_path_mkposix(buffer_out);
git_path_string_to_dir(buffer_out, size); /* append trailing slash */
return 0;
}
int p_rename(const char *from, const char *to)
{
if (!link(from, to)) {
p_unlink(from);
return 0;
}
if (!rename(from, to))
return 0;
return -1;
}
#endif /* GIT_WIN32 */
int p_read(git_file fd, void *buf, size_t cnt)
{
char *b = buf;
while (cnt) {
ssize_t r;
#ifdef GIT_WIN32
assert((size_t)((unsigned int)cnt) == cnt);
r = read(fd, b, (unsigned int)cnt);
#else
r = read(fd, b, cnt);
#endif
if (r < 0) {
if (errno == EINTR || errno == EAGAIN)
continue;
return -1;
}
if (!r)
break;
cnt -= r;
b += r;
}
return (int)(b - (char *)buf);
}
int p_write(git_file fd, const void *buf, size_t cnt)
{
const char *b = buf;
while (cnt) {
ssize_t r;
#ifdef GIT_WIN32
assert((size_t)((unsigned int)cnt) == cnt);
r = write(fd, b, (unsigned int)cnt);
#else
r = write(fd, b, cnt);
#endif
if (r < 0) {
if (errno == EINTR || GIT_ISBLOCKED(errno))
continue;
return -1;
}
if (!r) {
errno = EPIPE;
return -1;
}
cnt -= r;
b += r;
}
return 0;
}
#ifdef NO_MMAP
#include "map.h"
long git__page_size(void)
{
/* dummy; here we don't need any alignment anyway */
return 4096;
}
int p_mmap(git_map *out, size_t len, int prot, int flags, int fd, git_off_t offset)
{
GIT_MMAP_VALIDATE(out, len, prot, flags);
out->data = NULL;
out->len = 0;
if ((prot & GIT_PROT_WRITE) && ((flags & GIT_MAP_TYPE) == GIT_MAP_SHARED)) {
giterr_set(GITERR_OS, "Trying to map shared-writeable");
return -1;
}
out->data = malloc(len);
GITERR_CHECK_ALLOC(out->data);
if ((p_lseek(fd, offset, SEEK_SET) < 0) || ((size_t)p_read(fd, out->data, len) != len)) {
giterr_set(GITERR_OS, "mmap emulation failed");
return -1;
}
out->len = len;
return 0;
}
int p_munmap(git_map *map)
{
assert(map != NULL);
free(map->data);
return 0;
}
#endif