Move mmap_full_file from osl.c to fd.c.

[paraslash.git] / fd.c

diff --git a/fd.c b/fd.c
index 22550286d57747ec90bcdc4aa050c8bea8259e65..83c6cd5b4d39c77f723aef5f67553b60d6653a31 100644 (file)
--- a/fd.c
+++ b/fd.c
@@ -4,7 +4,7 @@
  * Licensed under the GPL v2. For licencing details see COPYING.
  */
 
  * Licensed under the GPL v2. For licencing details see COPYING.
  */
 

-/** \file fd.c helper functions for file descriptor handling */
+/** \file fd.c Helper functions for file descriptor handling. */

 
 #include <sys/types.h>
 #include <dirent.h>
 
 #include <sys/types.h>
 #include <dirent.h>


@@ -14,10 +14,11 @@
 
 #include "para.h"
 #include "error.h"
 
 #include "para.h"
 #include "error.h"

+

 /**
 /**

- * check whether a file exists
+ * Check whether a file exists.

  *
  *

- * \param fn the file name
+ * \param fn The file name.

  *
  * \return Non-zero iff file exists.
  */
  *
  * \return Non-zero iff file exists.
  */


@@ -78,16 +79,16 @@ int mark_fd_nonblock(int fd)
 }
 
 /**
 }
 
 /**

- * set a file descriptor in a fd_set
+ * Set a file descriptor in a fd_set.

  *
  *

- * \param fd the file descriptor to be set
- * \param fds the file descriptor set
- * \param max_fileno highest-numbered file descriptor
+ * \param fd The file descriptor to be set.
+ * \param fds The file descriptor set.
+ * \param max_fileno Highest-numbered file descriptor.

  *
  * This wrapper for FD_SET() passes its first two arguments to \p FD_SET. Upon
  * return, \a max_fileno contains the maximum of the old_value and \a fd.
  *
  *
  * This wrapper for FD_SET() passes its first two arguments to \p FD_SET. Upon
  * return, \a max_fileno contains the maximum of the old_value and \a fd.
  *

- * \sa para_select
+ * \sa para_select.

 */
 void para_fd_set(int fd, fd_set *fds, int *max_fileno)
 {
 */
 void para_fd_set(int fd, fd_set *fds, int *max_fileno)
 {


@@ -110,10 +111,11 @@ void para_fd_set(int fd, fd_set *fds, int *max_fileno)
 }
 
 /**
 }
 
 /**

-* 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
+* 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
 *
 * \return Unlike the standard fgets() function, an integer value
 * is returned. On success, this function returns 1. On errors, -E_FGETS


@@ -139,12 +141,12 @@ again:
 /**
  * Paraslash's wrapper for mmap.
  *
 /**
  * Paraslash's wrapper for mmap.
  *

- * \param length number of bytes to mmap
- * \param prot either PROT_NONE or the bitwise OR of one or more of
- * PROT_EXEC PROT_READ PROT_WRITE
- * \param flags exactly one of MAP_SHARED and MAP_PRIVATE
- * \param fd the file to mmap from
- * \param offset mmap start
+ * \param length Number of bytes to mmap.
+ * \param prot Either PROT_NONE or the bitwise OR of one or more of
+ * PROT_EXEC PROT_READ PROT_WRITE.
+ * \param flags Exactly one of MAP_SHARED and MAP_PRIVATE.
+ * \param fd The file to mmap from.
+ * \param offset Mmap start.

  *
  * \return This function either returns a valid pointer to the mapped area
  * or calls exit() on errors.
  *
  * \return This function either returns a valid pointer to the mapped area
  * or calls exit() on errors.


@@ -167,8 +169,8 @@ void *para_mmap(size_t length, int prot, int flags, int fd, off_t offset)
  * \param flags The usual open(2) flags.
  * \param mode Specifies the permissions to use.
  *
  * \param flags The usual open(2) flags.
  * \param mode Specifies the permissions to use.
  *

- * The mode parameter must be specified when O_CREAT is in the flags, and is ignored
- * otherwise.
+ * The mode parameter must be specified when O_CREAT is in the flags, and is
+ * ignored otherwise.

  *
  * \return The file descriptor on success, negative on errors.
  *
  *
  * \return The file descriptor on success, negative on errors.
  *


@@ -186,9 +188,9 @@ int para_open(const char *path, int flags, mode_t mode)
 /**
  * Wrapper for chdir(2).
  *
 /**
  * Wrapper for chdir(2).
  *

- * \param path the specified directory.
+ * \param path The specified directory.

  *
  *

- * \return Positive on success, negative on errors.
+ * \return Standard.

  */
 int para_chdir(const char *path)
 {
  */
 int para_chdir(const char *path)
 {


@@ -241,7 +243,6 @@ int para_opendir(const char *dirname, DIR **dir, int *cwd)
                return 1;
        ret = -ERRNO_TO_PARA_ERROR(errno);
 /* Ignore return value of fchdir() and close(). We're busted anyway. */
                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:
        if (cwd)
                fchdir(*cwd);
 close_cwd:


@@ -253,7 +254,7 @@ close_cwd:
 /**
  * A wrapper for fchdir().
  *
 /**
  * A wrapper for fchdir().
  *

- * \param fd An open file descriptor
+ * \param fd An open file descriptor.

  *
  * \return Standard.
  */
  *
  * \return Standard.
  */


@@ -278,3 +279,56 @@ int para_mkdir(const char *path, mode_t mode)
                return 1;
        return -ERRNO_TO_PARA_ERROR(errno);
 }
                return 1;
        return -ERRNO_TO_PARA_ERROR(errno);
 }

+
+/**
+ * Map a file into memory.
+ *
+ * \param path Name of the regular file to map.
+ * \param open_mode Either \p O_RDONLY or \p O_RDWR.
+ * \param obj On success, the mapping is returned here.
+ *
+ * \return Positive on success, negative on errors. Possible errors include: \p
+ * E_FSTAT, any errors returned by para_open(), \p E_EMPTY, \p E_MMAP.
+ *
+ * \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;
+}