diff options
Diffstat (limited to 'libreport/src/lib/copyfd.c')
| -rw-r--r-- | libreport/src/lib/copyfd.c | 172 |
1 files changed, 172 insertions, 0 deletions
diff --git a/libreport/src/lib/copyfd.c b/libreport/src/lib/copyfd.c new file mode 100644 index 00000000..8d805069 --- /dev/null +++ b/libreport/src/lib/copyfd.c @@ -0,0 +1,172 @@ +/* + Copyright (C) 2010 ABRT team + Copyright (C) 2010 RedHat Inc + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 2 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License along + with this program; if not, write to the Free Software Foundation, Inc., + 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. +*/ + +/* + * Utility routines. + * + */ +#include "libreport.h" + +#define CONFIG_FEATURE_COPYBUF_KB 4 + +static const char msg_write_error[] = "write error"; +static const char msg_read_error[] = "read error"; + +static off_t full_fd_action(int src_fd, int dst_fd, off_t size, int flags) +{ + int status = -1; + off_t total = 0; + int last_was_seek = 0; +#if CONFIG_FEATURE_COPYBUF_KB <= 4 + char buffer[CONFIG_FEATURE_COPYBUF_KB * 1024]; + enum { buffer_size = sizeof(buffer) }; +#else + char *buffer; + int buffer_size; + + /* We want page-aligned buffer, just in case kernel is clever + * and can do page-aligned io more efficiently */ + buffer = mmap(NULL, CONFIG_FEATURE_COPYBUF_KB * 1024, + PROT_READ | PROT_WRITE, + MAP_PRIVATE | MAP_ANON, + /* ignored: */ -1, 0); + buffer_size = CONFIG_FEATURE_COPYBUF_KB * 1024; + if (buffer == MAP_FAILED) { + buffer = alloca(4 * 1024); + buffer_size = 4 * 1024; + } +#endif + + if (src_fd < 0) + goto out; + + if (!size) { + size = buffer_size; + status = 1; /* copy until eof */ + } + + while (1) { + ssize_t rd; + + rd = safe_read(src_fd, buffer, size > buffer_size ? buffer_size : size); + + if (!rd) { /* eof - all done */ + if (last_was_seek) { + if (lseek(dst_fd, -1, SEEK_CUR) < 0 + || safe_write(dst_fd, "", 1) != 1 + ) { + perror_msg("%s", msg_write_error); + break; + } + } + status = 0; + break; + } + if (rd < 0) { + perror_msg("%s", msg_read_error); + break; + } + /* dst_fd == -1 is a fake, else... */ + if (dst_fd >= 0) { + if (flags & COPYFD_SPARSE) { + ssize_t cnt = rd; + while (--cnt >= 0) + if (buffer[cnt] != 0) + goto need2write; + if (lseek(dst_fd, rd, SEEK_CUR) < 0) { + flags &= ~COPYFD_SPARSE; + goto need2write; + } + last_was_seek = 1; + } else { + need2write: + { + ssize_t wr = full_write(dst_fd, buffer, rd); + if (wr < rd) { + perror_msg("%s", msg_write_error); + break; + } + last_was_seek = 0; + } + } + } + total += rd; + if (status < 0) { /* if we aren't copying till EOF... */ + size -= rd; + if (!size) { + /* 'size' bytes copied - all done */ + status = 0; + break; + } + } + } + out: + +#if CONFIG_FEATURE_COPYBUF_KB > 4 + if (buffer_size != 4 * 1024) + munmap(buffer, buffer_size); +#endif + return status ? -1 : total; +} + +off_t copyfd_size(int fd1, int fd2, off_t size, int flags) +{ + if (size) { + return full_fd_action(fd1, fd2, size, flags); + } + return 0; +} + +void copyfd_exact_size(int fd1, int fd2, off_t size) +{ + off_t sz = copyfd_size(fd1, fd2, size, /*flags:*/ 0); + if (sz == size) + return; + if (sz != -1) + error_msg_and_die("short read"); + /* if sz == -1, copyfd_XX already complained */ + xfunc_die(); +} + +off_t copyfd_eof(int fd1, int fd2, int flags) +{ + return full_fd_action(fd1, fd2, 0, flags); +} + +off_t copy_file(const char *src_name, const char *dst_name, int mode) +{ + off_t r; + int src = open(src_name, O_RDONLY); + if (src < 0) + { + perror_msg("Can't open '%s'", src_name); + return -1; + } + int dst = open(dst_name, O_WRONLY | O_TRUNC | O_CREAT, mode); + if (dst < 0) + { + close(src); + perror_msg("Can't open '%s'", dst_name); + return -1; + } + r = copyfd_eof(src, dst, /*flags:*/ 0); + close(src); + close(dst); + return r; +} |