rerere: refactor rerere logic to make it independent from I/O
This splits the handle_file() function into in-core part and I/O parts of the logic to create the preimage, so that we can compute the conflict identifier without having to use temporary files. Earlier, I thought the output from handle_file() should also be refactored, but it is always about writing preimage (or thisimage) that is used for later three-way merge, so it is saner to keep it to always write to FILE *. Signed-off-by: Junio C Hamano <gitster@pobox.com>
Junio C Hamano committed
Dec 25, 2009 at 14:34 UTC
27d6b08536838fff0e3568a57cc622ca1c39bf01
1 file changed
+76
-35
rerere.c
+76
-35
@@ -83,8 +83,37 @@ static inline void ferr_puts(const char *s, FILE *fp, int *err)
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ferr_write(s, strlen(s), fp, err);
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}
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-static int handle_file(const char *path,
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- unsigned char *sha1, const char *output)
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+struct rerere_io {
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+ int (*getline)(struct strbuf *, struct rerere_io *);
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+ FILE *output;
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+ int wrerror;
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+ /* some more stuff */
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+};
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+
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+static void rerere_io_putstr(const char *str, struct rerere_io *io)
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+{
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+ if (io->output)
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+ ferr_puts(str, io->output, &io->wrerror);
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+}
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+
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+static void rerere_io_putmem(const char *mem, size_t sz, struct rerere_io *io)
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+{
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+ if (io->output)
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+ ferr_write(mem, sz, io->output, &io->wrerror);
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+}
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+
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+struct rerere_io_file {
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+ struct rerere_io io;
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+ FILE *input;
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+};
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+
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+static int rerere_file_getline(struct strbuf *sb, struct rerere_io *io_)
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+{
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+ struct rerere_io_file *io = (struct rerere_io_file *)io_;
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+ return strbuf_getwholeline(sb, io->input, '\n');
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+}
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+
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+static int handle_path(unsigned char *sha1, struct rerere_io *io)
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{
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git_SHA_CTX ctx;
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int hunk_no = 0;
@@ -93,25 +122,11 @@ static int handle_file(const char *path,
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} hunk = RR_CONTEXT;
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struct strbuf one = STRBUF_INIT, two = STRBUF_INIT;
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struct strbuf buf = STRBUF_INIT;
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- FILE *f = fopen(path, "r");
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- FILE *out = NULL;
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- int wrerror = 0;
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-
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- if (!f)
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- return error("Could not open %s", path);
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-
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- if (output) {
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- out = fopen(output, "w");
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- if (!out) {
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- fclose(f);
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- return error("Could not write %s", output);
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- }
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- }
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if (sha1)
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git_SHA1_Init(&ctx);
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- while (!strbuf_getwholeline(&buf, f, '\n')) {
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+ while (!io->getline(&buf, io)) {
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if (!prefixcmp(buf.buf, "<<<<<<< ")) {
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if (hunk != RR_CONTEXT)
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goto bad;
@@ -131,13 +146,11 @@ static int handle_file(const char *path,
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strbuf_swap(&one, &two);
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hunk_no++;
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hunk = RR_CONTEXT;
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- if (out) {
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- ferr_puts("<<<<<<<\n", out, &wrerror);
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- ferr_write(one.buf, one.len, out, &wrerror);
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- ferr_puts("=======\n", out, &wrerror);
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- ferr_write(two.buf, two.len, out, &wrerror);
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- ferr_puts(">>>>>>>\n", out, &wrerror);
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- }
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+ rerere_io_putstr("<<<<<<<\n", io);
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+ rerere_io_putmem(one.buf, one.len, io);
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+ rerere_io_putstr("=======\n", io);
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+ rerere_io_putmem(two.buf, two.len, io);
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+ rerere_io_putstr(">>>>>>>\n", io);
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if (sha1) {
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git_SHA1_Update(&ctx, one.buf ? one.buf : "",
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one.len + 1);
@@ -152,8 +165,8 @@ static int handle_file(const char *path,
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; /* discard */
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else if (hunk == RR_SIDE_2)
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strbuf_addstr(&two, buf.buf);
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- else if (out)
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- ferr_puts(buf.buf, out, &wrerror);
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+ else
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+ rerere_io_putstr(buf.buf, io);
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continue;
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bad:
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hunk = 99; /* force error exit */
@@ -163,21 +176,49 @@ static int handle_file(const char *path,
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strbuf_release(&two);
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strbuf_release(&buf);
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- fclose(f);
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- if (wrerror)
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- error("There were errors while writing %s (%s)",
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- path, strerror(wrerror));
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- if (out && fclose(out))
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- wrerror = error("Failed to flush %s: %s",
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- path, strerror(errno));
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if (sha1)
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git_SHA1_Final(sha1, &ctx);
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- if (hunk != RR_CONTEXT) {
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+ if (hunk != RR_CONTEXT)
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+ return -1;
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+ return hunk_no;
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+}
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+
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+static int handle_file(const char *path, unsigned char *sha1, const char *output)
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+{
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+ int hunk_no = 0;
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+ struct rerere_io_file io;
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+
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+ memset(&io, 0, sizeof(io));
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+ io.io.getline = rerere_file_getline;
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+ io.input = fopen(path, "r");
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+ io.io.wrerror = 0;
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+ if (!io.input)
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+ return error("Could not open %s", path);
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+
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+ if (output) {
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+ io.io.output = fopen(output, "w");
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+ if (!io.io.output) {
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+ fclose(io.input);
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+ return error("Could not write %s", output);
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+ }
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+ }
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+
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+ hunk_no = handle_path(sha1, (struct rerere_io *)&io);
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+
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+ fclose(io.input);
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+ if (io.io.wrerror)
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+ error("There were errors while writing %s (%s)",
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+ path, strerror(io.io.wrerror));
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+ if (io.io.output && fclose(io.io.output))
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+ io.io.wrerror = error("Failed to flush %s: %s",
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+ path, strerror(errno));
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+
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+ if (hunk_no < 0) {
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if (output)
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unlink_or_warn(output);
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return error("Could not parse conflict hunks in %s", path);
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}
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- if (wrerror)
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+ if (io.io.wrerror)
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return -1;
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return hunk_no;
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}