Make things a little less confusing by making fill_buffer self-contained

and return both the buffer and amount filled rather than having it
modify the input struct and return a value.

diff --git a/usr.bin/file/file.c b/usr.bin/file/file.c
index 7402fa0..406e64b 100644 (file)
--- a/usr.bin/file/file.c
+++ b/usr.bin/file/file.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: file.c,v 1.41 2015/05/29 11:03:37 nicm Exp $ */
+/* $OpenBSD: file.c,v 1.42 2015/05/29 11:59:01 nicm Exp $ */
 
 /*
  * Copyright (c) 2015 Nicholas Marriott <nicm@openbsd.org>
@@ -371,7 +371,7 @@ child(int fd, pid_t parent, int argc, char **argv)
 }
 
 static void *
-fill_buffer(struct input_file *inf)
+fill_buffer(int fd, size_t size, size_t *used)
 {
        static void     *buffer;
        ssize_t          got;
@@ -382,9 +382,9 @@ fill_buffer(struct input_file *inf)
                buffer = xmalloc(FILE_READ_SIZE);
 
        next = buffer;
-       left = inf->size;
+       left = size;
        while (left != 0) {
-               got = read(inf->fd, next, left);
+               got = read(fd, next, left);
                if (got == -1) {
                        if (errno == EINTR)
                                continue;
@@ -395,13 +395,15 @@ fill_buffer(struct input_file *inf)
                next = (char *)next + got;
                left -= got;
        }
-       inf->size -= left;
+       *used = size - left;
        return buffer;
 }
 
 static int
 load_file(struct input_file *inf)
 {
+       size_t  used;
+
        inf->size = inf->msg->sb.st_size;
        if (inf->size > FILE_READ_SIZE)
                inf->size = FILE_READ_SIZE;
@@ -414,12 +416,13 @@ load_file(struct input_file *inf)
 
        inf->base = mmap(NULL, inf->size, PROT_READ, MAP_PRIVATE, inf->fd, 0);
        if (inf->base == MAP_FAILED) {
-               inf->base = fill_buffer(inf);
+               inf->base = fill_buffer(inf->fd, inf->size, &used);
                if (inf->base == NULL) {
                        xasprintf(&inf->result, "cannot read '%s' (%s)",
                            inf->path, strerror(errno));
                        return (1);
                }
+               inf->size = used;
        } else
                inf->mapped = 1;
        return (0);