vcs-svn: make buffer_skip_bytes return length read

Currently there is no way to detect when input ended if it ended
early during buffer_skip_bytes.  Tell the calling program how many
bytes were actually skipped for easier debugging.

Existing callers will still ignore early EOF.

Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: David Barr <david.barr@cordelta.com>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>

diff --git a/vcs-svn/line_buffer.c b/vcs-svn/line_buffer.c
index 747de07e6b4608d9d1ec68c9dc41d89aec552330..39d52b88b754338f7ad86cb71c1b7998f110f272 100644 (file)
--- a/vcs-svn/line_buffer.c
+++ b/vcs-svn/line_buffer.c
@@ -120,15 +120,16 @@ void buffer_copy_bytes(struct line_buffer *buf, off_t len)
        }
 }
 
-void buffer_skip_bytes(struct line_buffer *buf, off_t len)
+off_t buffer_skip_bytes(struct line_buffer *buf, off_t nbytes)
 {
        char byte_buffer[COPY_BUFFER_LEN];
-       uint32_t in;
-       while (len > 0 && !feof(buf->infile) && !ferror(buf->infile)) {
-               in = len < COPY_BUFFER_LEN ? len : COPY_BUFFER_LEN;
-               in = fread(byte_buffer, 1, in, buf->infile);
-               len -= in;
+       off_t done = 0;
+       while (done < nbytes && !feof(buf->infile) && !ferror(buf->infile)) {
+               off_t len = nbytes - done;
+               size_t in = len < COPY_BUFFER_LEN ? len : COPY_BUFFER_LEN;
+               done += fread(byte_buffer, 1, in, buf->infile);
        }
+       return done;
 }
 
 void buffer_reset(struct line_buffer *buf)

diff --git a/vcs-svn/line_buffer.h b/vcs-svn/line_buffer.h
index a090dd6874ebae4c2a46da32c62260159f210a62..7d10f9c751656ab05a22438bbd7eb52fa9573a38 100644 (file)
--- a/vcs-svn/line_buffer.h
+++ b/vcs-svn/line_buffer.h
@@ -27,6 +27,6 @@ char *buffer_read_string(struct line_buffer *buf, uint32_t len);
 int buffer_read_char(struct line_buffer *buf);
 void buffer_read_binary(struct line_buffer *buf, struct strbuf *sb, uint32_t len);
 void buffer_copy_bytes(struct line_buffer *buf, off_t len);
-void buffer_skip_bytes(struct line_buffer *buf, off_t len);
+off_t buffer_skip_bytes(struct line_buffer *buf, off_t len);
 
 #endif

diff --git a/vcs-svn/line_buffer.txt b/vcs-svn/line_buffer.txt
index e89cc41d562448ad65a42b039dcf06a8c38e3335..4ef0755cf53e4ee220f1906be7c0cd54ff3265ab 100644 (file)
--- a/vcs-svn/line_buffer.txt
+++ b/vcs-svn/line_buffer.txt
@@ -76,7 +76,8 @@ Functions
 
 `buffer_skip_bytes`::
        Discards `len` bytes from the input stream (stopping early
-       if necessary because of an error or eof).
+       if necessary because of an error or eof).  Return value is
+       the number of bytes successfully read.
 
 `buffer_reset`::
        Deallocates non-static buffers.