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-rw-r--r--count-delta.c72
1 files changed, 0 insertions, 72 deletions
diff --git a/count-delta.c b/count-delta.c
deleted file mode 100644
index 058a2aa..0000000
--- a/count-delta.c
+++ /dev/null
@@ -1,72 +0,0 @@
-/*
- * Copyright (C) 2005 Junio C Hamano
- * The delta-parsing part is almost straight copy of patch-delta.c
- * which is (C) 2005 Nicolas Pitre <nico@cam.org>.
- */
-#include <stdlib.h>
-#include <string.h>
-#include <limits.h>
-#include "delta.h"
-#include "count-delta.h"
-
-/*
- * NOTE. We do not _interpret_ delta fully. As an approximation, we
- * just count the number of bytes that are copied from the source, and
- * the number of literal data bytes that are inserted.
- *
- * Number of bytes that are _not_ copied from the source is deletion,
- * and number of inserted literal bytes are addition, so sum of them
- * is the extent of damage.
- */
-int count_delta(void *delta_buf, unsigned long delta_size,
- unsigned long *src_copied, unsigned long *literal_added)
-{
- unsigned long copied_from_source, added_literal;
- const unsigned char *data, *top;
- unsigned char cmd;
- unsigned long src_size, dst_size, out;
-
- if (delta_size < DELTA_SIZE_MIN)
- return -1;
-
- data = delta_buf;
- top = delta_buf + delta_size;
-
- src_size = get_delta_hdr_size(&data);
- dst_size = get_delta_hdr_size(&data);
-
- added_literal = copied_from_source = out = 0;
- while (data < top) {
- cmd = *data++;
- if (cmd & 0x80) {
- unsigned long cp_off = 0, cp_size = 0;
- if (cmd & 0x01) cp_off = *data++;
- if (cmd & 0x02) cp_off |= (*data++ << 8);
- if (cmd & 0x04) cp_off |= (*data++ << 16);
- if (cmd & 0x08) cp_off |= (*data++ << 24);
- if (cmd & 0x10) cp_size = *data++;
- if (cmd & 0x20) cp_size |= (*data++ << 8);
- if (cmd & 0x40) cp_size |= (*data++ << 16);
- if (cp_size == 0) cp_size = 0x10000;
-
- copied_from_source += cp_size;
- out += cp_size;
- } else {
- /* write literal into dst */
- added_literal += cmd;
- out += cmd;
- data += cmd;
- }
- }
-
- /* sanity check */
- if (data != top || out != dst_size)
- return -1;
-
- /* delete size is what was _not_ copied from source.
- * edit size is that and literal additions.
- */
- *src_copied = copied_from_source;
- *literal_added = added_literal;
- return 0;
-}