/*
- * Copyright (C) 2006-2007 Andre Noll <maan@systemlinux.org>
+ * Copyright (C) 2006-2008 Andre Noll <maan@systemlinux.org>
*
* Licensed under the GPL v2. For licencing details see COPYING.
*/
#include "para.h"
#include "error.h"
+/**
+ * Write a buffer to a file descriptor, re-write on short writes.
+ *
+ * \param fd The file descriptor.
+ * \param buf The buffer to be sent.
+ * \param len The length of \a buf.
+ *
+ * \return Standard. In any case, the number of bytes that have been written is
+ * stored in \a len.
+ */
+int write_all(int fd, const char *buf, size_t *len)
+{
+ size_t total = *len;
+
+ assert(total);
+ *len = 0;
+ while (*len < total) {
+ int ret = write(fd, buf + *len, total - *len);
+ if (ret == -1)
+ return -ERRNO_TO_PARA_ERROR(errno);
+ *len += ret;
+ }
+ return 1;
+}
+
/**
* Check whether a file exists.
*
return ret;
}
+/**
+ * Set a file descriptor to blocking mode.
+ *
+ * \param fd The file descriptor.
+ *
+ * \return Standard.
+ */
+__must_check int mark_fd_blocking(int fd)
+{
+ int flags = fcntl(fd, F_GETFL);
+ if (flags < 0)
+ return -ERRNO_TO_PARA_ERROR(errno);
+ flags = fcntl(fd, F_SETFL, ((long)flags) & ~O_NONBLOCK);
+ if (flags < 0)
+ return -ERRNO_TO_PARA_ERROR(errno);
+ return 1;
+}
+
/**
* Set a file descriptor to non-blocking mode.
*
*
* \return Standard.
*/
-int mark_fd_nonblock(int fd)
+__must_check int mark_fd_nonblocking(int fd)
{
int flags = fcntl(fd, F_GETFL);
if (flags < 0)
}
/**
-* Paraslash's wrapper for fgets(3).
-
-* \param line Pointer to the buffer to store the line.
-* \param size The size of the buffer given by \a line.
-* \param f The stream to read from.
-*
-* \return Unlike the standard fgets() function, an integer value
-* is returned. On success, this function returns 1. On errors, -E_FGETS
-* is returned. A zero return value indicates an end of file condition.
-*/
+ * Paraslash's wrapper for fgets(3).
+ *
+ * \param line Pointer to the buffer to store the line.
+ * \param size The size of the buffer given by \a line.
+ * \param f The stream to read from.
+ *
+ * \return Unlike the standard fgets() function, an integer value
+ * is returned. On success, this function returns 1. On errors, -E_FGETS
+ * is returned. A zero return value indicates an end of file condition.
+ */
__must_check int para_fgets(char *line, int size, FILE *f)
{
again:
return 1;
ret = -ERRNO_TO_PARA_ERROR(errno);
/* Ignore return value of fchdir() and close(). We're busted anyway. */
-change_to_orig_dir:
if (cwd)
fchdir(*cwd);
close_cwd:
return 1;
return -ERRNO_TO_PARA_ERROR(errno);
}
+
+/**
+ * Open a file and map it into memory.
+ *
+ * \param path Name of the regular file to map.
+ * \param open_mode Either \p O_RDONLY or \p O_RDWR.
+ * \param map On success, the mapping is returned here.
+ * \param size size of the mapping.
+ * \param fd_ptr The file descriptor of the mapping.
+ *
+ * If \a fd_ptr is \p NULL, the file descriptor resulting from the underlying
+ * open call is closed after mmap(). Otherwise the file is kept open and the
+ * file descriptor is returned in \a fd_ptr.
+ *
+ * \return Standard.
+ *
+ * \sa para_open(), mmap(2).
+ */
+int mmap_full_file(const char *path, int open_mode, void **map,
+ size_t *size, int *fd_ptr)
+{
+ int fd, ret, mmap_prot, mmap_flags;
+ struct stat file_status;
+
+ if (open_mode == O_RDONLY) {
+ mmap_prot = PROT_READ;
+ mmap_flags = MAP_PRIVATE;
+ } else {
+ mmap_prot = PROT_READ | PROT_WRITE;
+ mmap_flags = MAP_SHARED;
+ }
+ ret = para_open(path, open_mode, 0);
+ if (ret < 0)
+ return ret;
+ fd = ret;
+ if (fstat(fd, &file_status) < 0) {
+ ret = -ERRNO_TO_PARA_ERROR(errno);
+ goto out;
+ }
+ *size = file_status.st_size;
+ ret = -E_EMPTY;
+ PARA_DEBUG_LOG("%s: size %zu\n", path, *size);
+ if (!*size)
+ goto out;
+ *map = mmap(NULL, *size, mmap_prot, mmap_flags, fd, 0);
+ if (*map == MAP_FAILED) {
+ *map = NULL;
+ ret = -E_MMAP;
+ goto out;
+ }
+ ret = 1;
+out:
+ if (ret < 0 || !fd_ptr)
+ close(fd);
+ else
+ *fd_ptr = fd;
+ return ret;
+}
+
+/**
+ * A wrapper for munmap(2).
+ *
+ * \param start The start address of the memory mapping.
+ * \param length The size of the mapping.
+ *
+ * \return Positive on success, \p -E_MUNMAP on errors.
+ *
+ * \sa munmap(2), mmap_full_file().
+ */
+int para_munmap(void *start, size_t length)
+{
+ int err;
+ if (munmap(start, length) >= 0)
+ return 1;
+ err = errno;
+ PARA_ERROR_LOG("munmap (%p/%zu) failed: %s\n", start, length,
+ strerror(err));
+ return -ERRNO_TO_PARA_ERROR(err);
+}
+
+/**
+ * Check a file descriptor for writability.
+ *
+ * \param fd The file descriptor.
+ *
+ * \return positive if fd is ready for writing, zero if it isn't, negative if
+ * an error occurred.
+ */
+
+int write_ok(int fd)
+{
+ struct timeval tv = {0, 0};
+ fd_set wfds;
+ int ret;
+again:
+ FD_ZERO(&wfds);
+ FD_SET(fd, &wfds);
+ tv.tv_sec = 0;
+ tv.tv_usec = 0;
+ ret = select(fd + 1, NULL, &wfds, NULL, &tv);
+ if (ret < 0 && errno == EINTR)
+ goto again;
+ return ret;
+}
projects / paraslash.git / blobdiff