update doc server to ctorm 1.8.1

Signed-off-by: ngn <ngn@ngn.tf>

doc/src/file.c

@@ -0,0 +1,56 @@
+#include <sys/mman.h>
+
+#include <stdlib.h>
+#include <unistd.h>
+
+#include <stdio.h>
+#include <fcntl.h>
+#include <errno.h>
+
+#include "file.h"
+
+file_t *file_load(int dirfd, char *path) {
+  if (NULL == path) {
+    errno = EINVAL;
+    return NULL;
+  }
+
+  file_t *file = NULL;
+  int     fd   = -1;
+
+  // open the taarget file
+  if ((fd = openat(dirfd, path, O_RDONLY)) < 0)
+    goto end; // errno set by open
+
+  // allocate a new file structure
+  if (NULL == (file = calloc(1, sizeof(file_t))))
+    goto end; // errno set by malloc
+
+  // calculate the file size
+  if ((file->size = lseek(fd, 0, SEEK_END)) < 0)
+    goto end;
+
+  // memory map the file
+  if (NULL ==
+      (file->content = mmap(0, file->size, PROT_READ, MAP_PRIVATE, fd, 0)))
+    goto end; // errno set by mmap
+
+end:
+  if (fd != -1)
+    close(fd);
+
+  if (NULL != file && NULL == file->content) {
+    free(file);
+    return NULL;
+  }
+
+  return file;
+}
+
+void file_free(file_t *file) {
+  if (NULL == file)
+    return;
+
+  munmap(file->content, file->size);
+  free(file);
+}