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Diffstat (limited to 'vcs-svn/svndiff.c')
-rw-r--r--vcs-svn/svndiff.c309
1 files changed, 0 insertions, 309 deletions
diff --git a/vcs-svn/svndiff.c b/vcs-svn/svndiff.c
deleted file mode 100644
index 75c753162a..0000000000
--- a/vcs-svn/svndiff.c
+++ /dev/null
@@ -1,309 +0,0 @@
-/*
- * Licensed under a two-clause BSD-style license.
- * See LICENSE for details.
- */
-
-#include "git-compat-util.h"
-#include "sliding_window.h"
-#include "line_buffer.h"
-#include "svndiff.h"
-
-/*
- * svndiff0 applier
- *
- * See http://svn.apache.org/repos/asf/subversion/trunk/notes/svndiff.
- *
- * svndiff0 ::= 'SVN\0' window*
- * window ::= int int int int int instructions inline_data;
- * instructions ::= instruction*;
- * instruction ::= view_selector int int
- * | copyfrom_data int
- * | packed_view_selector int
- * | packed_copyfrom_data
- * ;
- * view_selector ::= copyfrom_source
- * | copyfrom_target
- * ;
- * copyfrom_source ::= # binary 00 000000;
- * copyfrom_target ::= # binary 01 000000;
- * copyfrom_data ::= # binary 10 000000;
- * packed_view_selector ::= # view_selector OR-ed with 6 bit value;
- * packed_copyfrom_data ::= # copyfrom_data OR-ed with 6 bit value;
- * int ::= highdigit* lowdigit;
- * highdigit ::= # binary 1000 0000 OR-ed with 7 bit value;
- * lowdigit ::= # 7 bit value;
- */
-
-#define INSN_MASK 0xc0
-#define INSN_COPYFROM_SOURCE 0x00
-#define INSN_COPYFROM_TARGET 0x40
-#define INSN_COPYFROM_DATA 0x80
-#define OPERAND_MASK 0x3f
-
-#define VLI_CONTINUE 0x80
-#define VLI_DIGIT_MASK 0x7f
-#define VLI_BITS_PER_DIGIT 7
-
-struct window {
- struct sliding_view *in;
- struct strbuf out;
- struct strbuf instructions;
- struct strbuf data;
-};
-
-#define WINDOW_INIT(w) { (w), STRBUF_INIT, STRBUF_INIT, STRBUF_INIT }
-
-static void window_release(struct window *ctx)
-{
- strbuf_release(&ctx->out);
- strbuf_release(&ctx->instructions);
- strbuf_release(&ctx->data);
-}
-
-static int write_strbuf(struct strbuf *sb, FILE *out)
-{
- if (fwrite(sb->buf, 1, sb->len, out) == sb->len) /* Success. */
- return 0;
- return error_errno("cannot write delta postimage");
-}
-
-static int error_short_read(struct line_buffer *input)
-{
- if (buffer_ferror(input))
- return error_errno("error reading delta");
- return error("invalid delta: unexpected end of file");
-}
-
-static int read_chunk(struct line_buffer *delta, off_t *delta_len,
- struct strbuf *buf, size_t len)
-{
- assert(*delta_len >= 0);
- strbuf_reset(buf);
- if (len > (uintmax_t) *delta_len ||
- buffer_read_binary(delta, buf, len) != len)
- return error_short_read(delta);
- *delta_len -= buf->len;
- return 0;
-}
-
-static int read_magic(struct line_buffer *in, off_t *len)
-{
- static const char magic[] = {'S', 'V', 'N', '\0'};
- struct strbuf sb = STRBUF_INIT;
-
- if (read_chunk(in, len, &sb, sizeof(magic))) {
- strbuf_release(&sb);
- return -1;
- }
- if (memcmp(sb.buf, magic, sizeof(magic))) {
- strbuf_release(&sb);
- return error("invalid delta: unrecognized file type");
- }
- strbuf_release(&sb);
- return 0;
-}
-
-static int read_int(struct line_buffer *in, uintmax_t *result, off_t *len)
-{
- uintmax_t rv = 0;
- off_t sz;
- for (sz = *len; sz; sz--) {
- const int ch = buffer_read_char(in);
- if (ch == EOF)
- break;
-
- rv <<= VLI_BITS_PER_DIGIT;
- rv += (ch & VLI_DIGIT_MASK);
- if (ch & VLI_CONTINUE)
- continue;
-
- *result = rv;
- *len = sz - 1;
- return 0;
- }
- return error_short_read(in);
-}
-
-static int parse_int(const char **buf, size_t *result, const char *end)
-{
- size_t rv = 0;
- const char *pos;
- for (pos = *buf; pos != end; pos++) {
- unsigned char ch = *pos;
-
- rv <<= VLI_BITS_PER_DIGIT;
- rv += (ch & VLI_DIGIT_MASK);
- if (ch & VLI_CONTINUE)
- continue;
-
- *result = rv;
- *buf = pos + 1;
- return 0;
- }
- return error("invalid delta: unexpected end of instructions section");
-}
-
-static int read_offset(struct line_buffer *in, off_t *result, off_t *len)
-{
- uintmax_t val;
- if (read_int(in, &val, len))
- return -1;
- if (val > maximum_signed_value_of_type(off_t))
- return error("unrepresentable offset in delta: %"PRIuMAX"", val);
- *result = val;
- return 0;
-}
-
-static int read_length(struct line_buffer *in, size_t *result, off_t *len)
-{
- uintmax_t val;
- if (read_int(in, &val, len))
- return -1;
- if (val > SIZE_MAX)
- return error("unrepresentable length in delta: %"PRIuMAX"", val);
- *result = val;
- return 0;
-}
-
-static int copyfrom_source(struct window *ctx, const char **instructions,
- size_t nbytes, const char *insns_end)
-{
- size_t offset;
- if (parse_int(instructions, &offset, insns_end))
- return -1;
- if (unsigned_add_overflows(offset, nbytes) ||
- offset + nbytes > ctx->in->width)
- return error("invalid delta: copies source data outside view");
- strbuf_add(&ctx->out, ctx->in->buf.buf + offset, nbytes);
- return 0;
-}
-
-static int copyfrom_target(struct window *ctx, const char **instructions,
- size_t nbytes, const char *instructions_end)
-{
- size_t offset;
- if (parse_int(instructions, &offset, instructions_end))
- return -1;
- if (offset >= ctx->out.len)
- return error("invalid delta: copies from the future");
- for (; nbytes > 0; nbytes--)
- strbuf_addch(&ctx->out, ctx->out.buf[offset++]);
- return 0;
-}
-
-static int copyfrom_data(struct window *ctx, size_t *data_pos, size_t nbytes)
-{
- const size_t pos = *data_pos;
- if (unsigned_add_overflows(pos, nbytes) ||
- pos + nbytes > ctx->data.len)
- return error("invalid delta: copies unavailable inline data");
- strbuf_add(&ctx->out, ctx->data.buf + pos, nbytes);
- *data_pos += nbytes;
- return 0;
-}
-
-static int parse_first_operand(const char **buf, size_t *out, const char *end)
-{
- size_t result = (unsigned char) *(*buf)++ & OPERAND_MASK;
- if (result) { /* immediate operand */
- *out = result;
- return 0;
- }
- return parse_int(buf, out, end);
-}
-
-static int execute_one_instruction(struct window *ctx,
- const char **instructions, size_t *data_pos)
-{
- unsigned int instruction;
- const char *insns_end = ctx->instructions.buf + ctx->instructions.len;
- size_t nbytes;
- assert(ctx);
- assert(instructions && *instructions);
- assert(data_pos);
-
- instruction = (unsigned char) **instructions;
- if (parse_first_operand(instructions, &nbytes, insns_end))
- return -1;
- switch (instruction & INSN_MASK) {
- case INSN_COPYFROM_SOURCE:
- return copyfrom_source(ctx, instructions, nbytes, insns_end);
- case INSN_COPYFROM_TARGET:
- return copyfrom_target(ctx, instructions, nbytes, insns_end);
- case INSN_COPYFROM_DATA:
- return copyfrom_data(ctx, data_pos, nbytes);
- default:
- return error("invalid delta: unrecognized instruction");
- }
-}
-
-static int apply_window_in_core(struct window *ctx)
-{
- const char *instructions;
- size_t data_pos = 0;
-
- /*
- * Fill ctx->out.buf using data from the source, target,
- * and inline data views.
- */
- for (instructions = ctx->instructions.buf;
- instructions != ctx->instructions.buf + ctx->instructions.len;
- )
- if (execute_one_instruction(ctx, &instructions, &data_pos))
- return -1;
- if (data_pos != ctx->data.len)
- return error("invalid delta: does not copy all inline data");
- return 0;
-}
-
-static int apply_one_window(struct line_buffer *delta, off_t *delta_len,
- struct sliding_view *preimage, FILE *out)
-{
- int rv = -1;
- struct window ctx = WINDOW_INIT(preimage);
- size_t out_len;
- size_t instructions_len;
- size_t data_len;
- assert(delta_len);
-
- /* "source view" offset and length already handled; */
- if (read_length(delta, &out_len, delta_len) ||
- read_length(delta, &instructions_len, delta_len) ||
- read_length(delta, &data_len, delta_len) ||
- read_chunk(delta, delta_len, &ctx.instructions, instructions_len) ||
- read_chunk(delta, delta_len, &ctx.data, data_len))
- goto error_out;
- strbuf_grow(&ctx.out, out_len);
- if (apply_window_in_core(&ctx))
- goto error_out;
- if (ctx.out.len != out_len) {
- rv = error("invalid delta: incorrect postimage length");
- goto error_out;
- }
- if (write_strbuf(&ctx.out, out))
- goto error_out;
- rv = 0;
-error_out:
- window_release(&ctx);
- return rv;
-}
-
-int svndiff0_apply(struct line_buffer *delta, off_t delta_len,
- struct sliding_view *preimage, FILE *postimage)
-{
- assert(delta && preimage && postimage && delta_len >= 0);
-
- if (read_magic(delta, &delta_len))
- return -1;
- while (delta_len) { /* For each window: */
- off_t pre_off = -1;
- size_t pre_len;
-
- if (read_offset(delta, &pre_off, &delta_len) ||
- read_length(delta, &pre_len, &delta_len) ||
- move_window(preimage, pre_off, pre_len) ||
- apply_one_window(delta, &delta_len, preimage, postimage))
- return -1;
- }
- return 0;
-}
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