src/lib/file-copy.c

	file-copy.c revision b978e532c217b51d398d1855893143b7bc0a73f3
/* Copyright (c) 2006 Timo Sirainen */

#include "lib.h"
#include "istream.h"
#include "ostream.h"
#include "file-copy.h"

#include <stdio.h>
#include <unistd.h>
#include <fcntl.h>

int file_copy(const char *srcpath, const char *destpath, bool try_hardlink)
{
    const char *tmppath;
    struct istream *input;
    struct ostream *output;
    int fd_in, fd_out;
    off_t ret;

    if (try_hardlink) {
        /* see if hardlinking works */
        if (link(srcpath, destpath) == 0 || errno == EEXIST)
            return 1;
        if (errno == ENOENT)
            return 0;
        if (!ECANTLINK(errno)) {
            i_error("link(%s, %s) failed: %m", srcpath, destpath);
            return -1;
        }

        /* fallback to manual copying */
    }

    fd_in = open(srcpath, O_RDONLY);
    if (fd_in == -1) {
        if (errno == ENOENT)
            return 0;
        i_error("open(%s) failed: %m", srcpath);
        return -1;
    }

    t_push();
    tmppath = t_strconcat(destpath, ".tmp", NULL);
    fd_out = open(tmppath, O_WRONLY | O_CREAT | O_TRUNC, 0644);
    if (fd_out == -1) {
        i_error("open(%s, O_CREAT) failed: %m", tmppath);
        (void)close(fd_in);
        t_pop();
        return -1;
    }
    input = i_stream_create_file(fd_in, default_pool, 0, FALSE);
    output = o_stream_create_file(fd_out, default_pool, 0, FALSE);

    while ((ret = o_stream_send_istream(output, input)) > 0) ;

    i_stream_destroy(&input);
    o_stream_destroy(&output);

    if (close(fd_in) < 0) {
        i_error("close(%s) failed: %m", srcpath);
        ret = -1;
    }
    if (close(fd_out) < 0) {
        i_error("close(%s) failed: %m", tmppath);
        ret = -1;
    }
    if (ret == 0) {
        if (rename(tmppath, destpath) < 0) {
            i_error("rename(%s, %s) failed: %m", tmppath, destpath);
            ret = -1;
        }
    }
    if (ret < 0)
        (void)unlink(tmppath);
    t_pop();
    return ret < 0 ? -1 : 1;
}