vi: don't keep fd open unnecessarily.

As soon as mmap() is done, we can close the fd. xmmap() also will exit
rather than return failure so we can remove that check, and fdlength()
will fall back to lseek() so there's no need to have the fallback in vi
itself.

Spotted because the `TT.fd = 0` in linelist_unload() seemed suspicious;
-1 would have been more natural.

1 files changed, 8 insertions, 14 deletions

diff --git a/toys/pending/vi.c b/toys/pending/vi.c
index b5f34e21..62cbbab0 100644
--- a/toys/pending/vi.c
+++ b/toys/pending/vi.c
@@ -41,7 +41,7 @@ GLOBALS(
     char* data;
   } yank;
 
-  int modified, fd;
+  int modified;
   size_t filesize;
 // mem_block contains RO data that is either original file as mmap
 // or heap allocated inserted data
@@ -509,8 +509,7 @@ static void linelist_unload()
 {
   llist_traverse((void *)TT.slices, llist_free_double);
   llist_traverse((void *)TT.text, block_list_free);
-  if (TT.fd) xclose(TT.fd);
-  TT.slices = 0, TT.text = 0, TT.fd = 0;
+  TT.slices = 0, TT.text = 0;
 }
 
 static int linelist_load(char *filename)
@@ -518,20 +517,15 @@ static int linelist_load(char *filename)
   if (!filename) filename = (char*)*toys.optargs;
 
   if (filename) {
-    int fd;
-    size_t len, size;
+    int fd = open(filename, O_RDONLY);
+    size_t size;
     char *data;
-    if ( (fd = open(filename, O_RDONLY)) <0) return 0;
 
-    size = fdlength(fd);
-    if (!(len = lseek(fd, 0, SEEK_END))) len = size;
-    lseek(fd, 0, SEEK_SET);
-
-    data = xmmap(0, size, PROT_READ, MAP_SHARED, fd, 0);
-    if (data == MAP_FAILED) return 0;
-    insert_str(data, 0, size, len, MMAP);
+    if (fd == -1) return 0;
+    data = xmmap(0, size = fdlength(fd), PROT_READ, MAP_SHARED, fd, 0);
+    xclose(fd);
+    insert_str(data, 0, size, size, MMAP);
     TT.filesize = text_filesize();
-    TT.fd = fd;
   }
 
   return 1;