vcs-svn: make buffer_copy_bytes return length read
Currently buffer_copy_bytes does not report to its caller whether it encountered an early end of file. Add a return value representing the number of bytes read (but not the number of bytes copied). This way all three unusual conditions can be distinguished: input error with buffer_ferror, output error with ferror(outfile), early end of input by checking the return value. 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>
Jonathan Nieder committed
Dec 28, 2010 at 04:26 UTC
26557fc1b37480d184a32de025b060aa1aa231db
2 files changed
+11
-10
vcs-svn/line_buffer.c
+9
-9
@@ -104,20 +104,20 @@ void buffer_read_binary(struct line_buffer *buf,
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strbuf_fread(sb, size, buf->infile);
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}
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-void buffer_copy_bytes(struct line_buffer *buf, off_t len)
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+off_t buffer_copy_bytes(struct line_buffer *buf, off_t nbytes)
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{
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char byte_buffer[COPY_BUFFER_LEN];
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- uint32_t in;
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- while (len > 0 && !feof(buf->infile) && !ferror(buf->infile)) {
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- in = len < COPY_BUFFER_LEN ? len : COPY_BUFFER_LEN;
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+ off_t done = 0;
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+ while (done < nbytes && !feof(buf->infile) && !ferror(buf->infile)) {
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+ off_t len = nbytes - done;
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+ size_t in = len < COPY_BUFFER_LEN ? len : COPY_BUFFER_LEN;
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in = fread(byte_buffer, 1, in, buf->infile);
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- len -= in;
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+ done += in;
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fwrite(byte_buffer, 1, in, stdout);
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- if (ferror(stdout)) {
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- buffer_skip_bytes(buf, len);
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- return;
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- }
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+ if (ferror(stdout))
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+ return done + buffer_skip_bytes(buf, nbytes - done);
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}
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+ return done;
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}
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off_t buffer_skip_bytes(struct line_buffer *buf, off_t nbytes)
vcs-svn/line_buffer.h
+2
-1
@@ -26,7 +26,8 @@ char *buffer_read_line(struct line_buffer *buf);
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char *buffer_read_string(struct line_buffer *buf, uint32_t len);
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int buffer_read_char(struct line_buffer *buf);
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void buffer_read_binary(struct line_buffer *buf, struct strbuf *sb, uint32_t len);
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-void buffer_copy_bytes(struct line_buffer *buf, off_t len);
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+/* Returns number of bytes read (not necessarily written). */
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+off_t buffer_copy_bytes(struct line_buffer *buf, off_t len);
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off_t buffer_skip_bytes(struct line_buffer *buf, off_t len);
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#endif