Move mmap_full_file from osl.c to fd.c.

[paraslash.git] / fd.c

diff --git a/fd.c b/fd.c
index 30483006be2e4df5e3c2c3cd02650430eb949dbb..83c6cd5b4d39c77f723aef5f67553b60d6653a31 100644 (file)
--- a/fd.c
+++ b/fd.c
@@ -279,3 +279,56 @@ int para_mkdir(const char *path, mode_t mode)
                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;
+}