Merge pull request #6061 from libgit2/ethomson/email

Introduce `git_email_create`; deprecate `git_diff_format_email`

5 files changed, 374 insertions, 173 deletions

diff --git a/src/buffer.c b/src/buffer.c
index ab2a6139a..a57df1284 100644
--- a/src/buffer.c
+++ b/src/buffer.c
@@ -600,6 +600,13 @@ void git_buf_shorten(git_buf *buf, size_t amount)
 		git_buf_clear(buf);
 }
 
+void git_buf_truncate_at_char(git_buf *buf, char separator)
+{
+	ssize_t idx = git_buf_find(buf, separator);
+	if (idx >= 0)
+		git_buf_truncate(buf, (size_t)idx);
+}
+
 void git_buf_rtruncate_at_char(git_buf *buf, char separator)
 {
 	ssize_t idx = git_buf_rfind_next(buf, separator);
diff --git a/src/buffer.h b/src/buffer.h
index 7faa9fdc8..a356bebea 100644
--- a/src/buffer.h
+++ b/src/buffer.h
@@ -171,6 +171,7 @@ void git_buf_consume_bytes(git_buf *buf, size_t len);
 void git_buf_consume(git_buf *buf, const char *end);
 void git_buf_truncate(git_buf *buf, size_t len);
 void git_buf_shorten(git_buf *buf, size_t amount);
+void git_buf_truncate_at_char(git_buf *buf, char separator);
 void git_buf_rtruncate_at_char(git_buf *path, char separator);
 
 /** General join with separator */
diff --git a/src/diff.c b/src/diff.c
index 4085c5f78..30b9f647a 100644
--- a/src/diff.c
+++ b/src/diff.c
@@ -7,11 +7,15 @@
 
 #include "diff.h"
 
-#include "git2/version.h"
-#include "diff_generate.h"
+#include "common.h"
 #include "patch.h"
+#include "email.h"
 #include "commit.h"
 #include "index.h"
+#include "diff_generate.h"
+
+#include "git2/version.h"
+#include "git2/email.h"
 
 struct patch_id_args {
 	git_hash_ctx ctx;
@@ -150,97 +154,14 @@ int git_diff_foreach(
 	return error;
 }
 
-static int diff_format_email_append_header_tobuf(
-	git_buf *out,
-	const git_oid *id,
-	const git_signature *author,
-	const char *summary,
-	const char *body,
-	size_t patch_no,
-	size_t total_patches,
-	bool exclude_patchno_marker)
-{
-	char idstr[GIT_OID_HEXSZ + 1];
-	char date_str[GIT_DATE_RFC2822_SZ];
-	int error = 0;
-
-	git_oid_fmt(idstr, id);
-	idstr[GIT_OID_HEXSZ] = '\0';
-
-	if ((error = git__date_rfc2822_fmt(date_str, sizeof(date_str),
-		&author->when)) < 0)
-		return error;
-
-	error = git_buf_printf(out,
-				"From %s Mon Sep 17 00:00:00 2001\n" \
-				"From: %s <%s>\n" \
-				"Date: %s\n" \
-				"Subject: ",
-				idstr,
-				author->name, author->email,
-				date_str);
-
-	if (error < 0)
-		return error;
-
-	if (!exclude_patchno_marker) {
-		if (total_patches == 1) {
-			error = git_buf_puts(out, "[PATCH] ");
-		} else {
-			error = git_buf_printf(out, "[PATCH %"PRIuZ"/%"PRIuZ"] ",
-				patch_no, total_patches);
-		}
-
-		if (error < 0)
-			return error;
-	}
-
-	error = git_buf_printf(out, "%s\n\n", summary);
-
-	if (body) {
-		git_buf_puts(out, body);
-
-		if (out->ptr[out->size - 1] != '\n')
-			git_buf_putc(out, '\n');
-	}
-
-	return error;
-}
-
-static int diff_format_email_append_patches_tobuf(
-	git_buf *out,
-	git_diff *diff)
-{
-	size_t i, deltas;
-	int error = 0;
-
-	deltas = git_diff_num_deltas(diff);
-
-	for (i = 0; i < deltas; ++i) {
-		git_patch *patch = NULL;
-
-		if ((error = git_patch_from_diff(&patch, diff, i)) >= 0)
-			error = git_patch_to_buf(out, patch);
-
-		git_patch_free(patch);
-
-		if (error < 0)
-			break;
-	}
-
-	return error;
-}
+#ifndef GIT_DEPRECATE_HARD
 
 int git_diff_format_email(
 	git_buf *out,
 	git_diff *diff,
 	const git_diff_format_email_options *opts)
 {
-	git_diff_stats *stats = NULL;
-	char *summary = NULL, *loc = NULL;
-	bool ignore_marker;
-	unsigned int format_flags = 0;
-	size_t allocsize;
+	git_email_create_options email_create_opts = GIT_EMAIL_CREATE_OPTIONS_INIT;
 	int error;
 
 	GIT_ASSERT_ARG(out);
@@ -251,64 +172,13 @@ int git_diff_format_email(
 		GIT_DIFF_FORMAT_EMAIL_OPTIONS_VERSION,
 		"git_format_email_options");
 
-	ignore_marker = (opts->flags &
-		GIT_DIFF_FORMAT_EMAIL_EXCLUDE_SUBJECT_PATCH_MARKER) != 0;
-
-	if (!ignore_marker) {
-		if (opts->patch_no > opts->total_patches) {
-			git_error_set(GIT_ERROR_INVALID,
-				"patch %"PRIuZ" out of range. max %"PRIuZ,
-				opts->patch_no, opts->total_patches);
-			return -1;
-		}
+	if ((opts->flags & GIT_DIFF_FORMAT_EMAIL_EXCLUDE_SUBJECT_PATCH_MARKER) != 0)
+		email_create_opts.subject_prefix = "";
 
-		if (opts->patch_no == 0) {
-			git_error_set(GIT_ERROR_INVALID,
-				"invalid patch no %"PRIuZ". should be >0", opts->patch_no);
-			return -1;
-		}
-	}
 
-	/* the summary we receive may not be clean.
-	 * it could potentially contain new line characters
-	 * or not be set, sanitize, */
-	if ((loc = strpbrk(opts->summary, "\r\n")) != NULL) {
-		size_t offset = 0;
-
-		if ((offset = (loc - opts->summary)) == 0) {
-			git_error_set(GIT_ERROR_INVALID, "summary is empty");
-			error = -1;
-			goto on_error;
-		}
-
-		GIT_ERROR_CHECK_ALLOC_ADD(&allocsize, offset, 1);
-		summary = git__calloc(allocsize, sizeof(char));
-		GIT_ERROR_CHECK_ALLOC(summary);
-
-		strncpy(summary, opts->summary, offset);
-	}
-
-	error = diff_format_email_append_header_tobuf(out,
-		opts->id, opts->author, summary == NULL ? opts->summary : summary,
-		opts->body, opts->patch_no, opts->total_patches, ignore_marker);
-
-	if (error < 0)
-		goto on_error;
-
-	format_flags = GIT_DIFF_STATS_FULL | GIT_DIFF_STATS_INCLUDE_SUMMARY;
-
-	if ((error = git_buf_puts(out, "---\n")) < 0 ||
-		(error = git_diff_get_stats(&stats, diff)) < 0 ||
-		(error = git_diff_stats_to_buf(out, stats, format_flags, 0)) < 0 ||
-		(error = git_buf_putc(out, '\n')) < 0 ||
-		(error = diff_format_email_append_patches_tobuf(out, diff)) < 0)
-			goto on_error;
-
-	error = git_buf_puts(out, "--\nlibgit2 " LIBGIT2_VERSION "\n\n");
-
-on_error:
-	git__free(summary);
-	git_diff_stats_free(stats);
+	error = git_email__append_from_diff(out, diff, opts->patch_no,
+		opts->total_patches, opts->id, opts->summary, opts->body,
+		opts->author, &email_create_opts);
 
 	return error;
 }
@@ -323,60 +193,43 @@ int git_diff_commit_as_email(
 	const git_diff_options *diff_opts)
 {
 	git_diff *diff = NULL;
-	git_diff_format_email_options opts =
-		GIT_DIFF_FORMAT_EMAIL_OPTIONS_INIT;
+	git_email_create_options opts = GIT_EMAIL_CREATE_OPTIONS_INIT;
+	const git_oid *commit_id;
+	const char *summary, *body;
+	const git_signature *author;
 	int error;
 
 	GIT_ASSERT_ARG(out);
 	GIT_ASSERT_ARG(repo);
 	GIT_ASSERT_ARG(commit);
 
-	opts.flags = flags;
-	opts.patch_no = patch_no;
-	opts.total_patches = total_patches;
-	opts.id = git_commit_id(commit);
-	opts.summary = git_commit_summary(commit);
-	opts.body = git_commit_body(commit);
-	opts.author = git_commit_author(commit);
+	commit_id = git_commit_id(commit);
+	summary = git_commit_summary(commit);
+	body = git_commit_body(commit);
+	author = git_commit_author(commit);
+
+	if ((flags & GIT_DIFF_FORMAT_EMAIL_EXCLUDE_SUBJECT_PATCH_MARKER) != 0)
+		opts.subject_prefix = "";
 
 	if ((error = git_diff__commit(&diff, repo, commit, diff_opts)) < 0)
 		return error;
 
-	error = git_diff_format_email(out, diff, &opts);
+	error = git_email_create_from_diff(out, diff, patch_no, total_patches, commit_id, summary, body, author, &opts);
 
 	git_diff_free(diff);
 	return error;
 }
 
-int git_diff_options_init(git_diff_options *opts, unsigned int version)
-{
-	GIT_INIT_STRUCTURE_FROM_TEMPLATE(
-		opts, version, git_diff_options, GIT_DIFF_OPTIONS_INIT);
-	return 0;
-}
-
-#ifndef GIT_DEPRECATE_HARD
 int git_diff_init_options(git_diff_options *opts, unsigned int version)
 {
 	return git_diff_options_init(opts, version);
 }
-#endif
 
-int git_diff_find_options_init(
-	git_diff_find_options *opts, unsigned int version)
-{
-	GIT_INIT_STRUCTURE_FROM_TEMPLATE(
-		opts, version, git_diff_find_options, GIT_DIFF_FIND_OPTIONS_INIT);
-	return 0;
-}
-
-#ifndef GIT_DEPRECATE_HARD
 int git_diff_find_init_options(
 	git_diff_find_options *opts, unsigned int version)
 {
 	return git_diff_find_options_init(opts, version);
 }
-#endif
 
 int git_diff_format_email_options_init(
 	git_diff_format_email_options *opts, unsigned int version)
@@ -387,14 +240,29 @@ int git_diff_format_email_options_init(
 	return 0;
 }
 
-#ifndef GIT_DEPRECATE_HARD
 int git_diff_format_email_init_options(
 	git_diff_format_email_options *opts, unsigned int version)
 {
 	return git_diff_format_email_options_init(opts, version);
 }
+
 #endif
 
+int git_diff_options_init(git_diff_options *opts, unsigned int version)
+{
+	GIT_INIT_STRUCTURE_FROM_TEMPLATE(
+		opts, version, git_diff_options, GIT_DIFF_OPTIONS_INIT);
+	return 0;
+}
+
+int git_diff_find_options_init(
+	git_diff_find_options *opts, unsigned int version)
+{
+	GIT_INIT_STRUCTURE_FROM_TEMPLATE(
+		opts, version, git_diff_find_options, GIT_DIFF_FIND_OPTIONS_INIT);
+	return 0;
+}
+
 static int flush_hunk(git_oid *result, git_hash_ctx *ctx)
 {
 	git_oid hash;
diff --git a/src/email.c b/src/email.c
new file mode 100644
index 000000000..8957d9a38
--- /dev/null
+++ b/src/email.c
@@ -0,0 +1,300 @@
+/*
+ * Copyright (C) the libgit2 contributors. All rights reserved.
+ *
+ * This file is part of libgit2, distributed under the GNU GPL v2 with
+ * a Linking Exception. For full terms see the included COPYING file.
+ */
+
+#include "email.h"
+
+#include "buffer.h"
+#include "common.h"
+#include "diff_generate.h"
+
+#include "git2/email.h"
+#include "git2/patch.h"
+#include "git2/version.h"
+
+/*
+ * Git uses a "magic" timestamp to indicate that an email message
+ * is from `git format-patch` (or our equivalent).
+ */
+#define EMAIL_TIMESTAMP "Mon Sep 17 00:00:00 2001"
+
+GIT_INLINE(int) include_prefix(
+	size_t patch_count,
+	git_email_create_options *opts)
+{
+	return ((!opts->subject_prefix || *opts->subject_prefix) ||
+	        (opts->flags & GIT_EMAIL_CREATE_ALWAYS_NUMBER) != 0 ||
+	        opts->reroll_number ||
+		(patch_count > 1 && !(opts->flags & GIT_EMAIL_CREATE_OMIT_NUMBERS)));
+}
+
+static int append_prefix(
+	git_buf *out,
+	size_t patch_idx,
+	size_t patch_count,
+	git_email_create_options *opts)
+{
+	const char *subject_prefix = opts->subject_prefix ?
+		opts->subject_prefix : "PATCH";
+
+	git_buf_putc(out, '[');
+
+	if (*subject_prefix)
+		git_buf_puts(out, subject_prefix);
+
+	if (opts->reroll_number) {
+		if (*subject_prefix)
+			git_buf_putc(out, ' ');
+
+		git_buf_printf(out, "v%" PRIuZ, opts->reroll_number);
+	}
+
+	if ((opts->flags & GIT_EMAIL_CREATE_ALWAYS_NUMBER) != 0 ||
+	    (patch_count > 1 && !(opts->flags & GIT_EMAIL_CREATE_OMIT_NUMBERS))) {
+		size_t start_number = opts->start_number ?
+			opts->start_number : 1;
+
+		if (*subject_prefix || opts->reroll_number)
+			git_buf_putc(out, ' ');
+
+		git_buf_printf(out, "%" PRIuZ "/%" PRIuZ,
+		               patch_idx + (start_number - 1),
+		               patch_count + (start_number - 1));
+	}
+
+	git_buf_puts(out, "]");
+
+	return git_buf_oom(out) ? -1 : 0;
+}
+
+static int append_subject(
+	git_buf *out,
+	size_t patch_idx,
+	size_t patch_count,
+	const char *summary,
+	git_email_create_options *opts)
+{
+	bool prefix = include_prefix(patch_count, opts);
+	size_t summary_len = summary ? strlen(summary) : 0;
+	int error;
+
+	if (summary_len) {
+		const char *nl = strchr(summary, '\n');
+
+		if (nl)
+			summary_len = (nl - summary);
+	}
+
+	if ((error = git_buf_puts(out, "Subject: ")) < 0)
+		return error;
+
+	if (prefix &&
+	    (error = append_prefix(out, patch_idx, patch_count, opts)) < 0)
+		return error;
+
+	if (prefix && summary_len && (error = git_buf_putc(out, ' ')) < 0)
+		return error;
+
+	if (summary_len &&
+	    (error = git_buf_put(out, summary, summary_len)) < 0)
+		return error;
+
+	return git_buf_putc(out, '\n');
+}
+
+static int append_header(
+	git_buf *out,
+	size_t patch_idx,
+	size_t patch_count,
+	const git_oid *commit_id,
+	const char *summary,
+	const git_signature *author,
+	git_email_create_options *opts)
+{
+	char id[GIT_OID_HEXSZ];
+	char date[GIT_DATE_RFC2822_SZ];
+	int error;
+
+	if ((error = git_oid_fmt(id, commit_id)) < 0 ||
+	    (error = git_buf_printf(out, "From %.*s %s\n", GIT_OID_HEXSZ, id, EMAIL_TIMESTAMP)) < 0 ||
+	    (error = git_buf_printf(out, "From: %s <%s>\n", author->name, author->email)) < 0 ||
+	    (error = git__date_rfc2822_fmt(date, sizeof(date), &author->when)) < 0 ||
+	    (error = git_buf_printf(out, "Date: %s\n", date)) < 0 ||
+	    (error = append_subject(out, patch_idx, patch_count, summary, opts)) < 0)
+		return error;
+
+	if ((error = git_buf_putc(out, '\n')) < 0)
+		return error;
+
+	return 0;
+}
+
+static int append_body(git_buf *out, const char *body)
+{
+	size_t body_len;
+	int error;
+
+	if (!body)
+		return 0;
+
+	body_len = strlen(body);
+
+	if ((error = git_buf_puts(out, body)) < 0)
+		return error;
+
+	if (body_len && body[body_len - 1] != '\n')
+		error = git_buf_putc(out, '\n');
+
+	return error;
+}
+
+static int append_diffstat(git_buf *out, git_diff *diff)
+{
+	git_diff_stats *stats = NULL;
+	unsigned int format_flags;
+	int error;
+
+	format_flags = GIT_DIFF_STATS_FULL | GIT_DIFF_STATS_INCLUDE_SUMMARY;
+
+	if ((error = git_diff_get_stats(&stats, diff)) == 0 &&
+	    (error = git_diff_stats_to_buf(out, stats, format_flags, 0)) == 0)
+		error = git_buf_putc(out, '\n');
+
+	git_diff_stats_free(stats);
+	return error;
+}
+
+static int append_patches(git_buf *out, git_diff *diff)
+{
+	size_t i, deltas;
+	int error = 0;
+
+	deltas = git_diff_num_deltas(diff);
+
+	for (i = 0; i < deltas; ++i) {
+		git_patch *patch = NULL;
+
+		if ((error = git_patch_from_diff(&patch, diff, i)) >= 0)
+			error = git_patch_to_buf(out, patch);
+
+		git_patch_free(patch);
+
+		if (error < 0)
+			break;
+	}
+
+	return error;
+}
+
+int git_email__append_from_diff(
+	git_buf *out,
+	git_diff *diff,
+	size_t patch_idx,
+	size_t patch_count,
+	const git_oid *commit_id,
+	const char *summary,
+	const char *body,
+	const git_signature *author,
+	const git_email_create_options *given_opts)
+{
+	git_email_create_options opts = GIT_EMAIL_CREATE_OPTIONS_INIT;
+	int error;
+
+	GIT_ASSERT_ARG(out);
+	GIT_ASSERT_ARG(diff);
+	GIT_ASSERT_ARG(!patch_idx || patch_idx <= patch_count);
+	GIT_ASSERT_ARG(commit_id);
+	GIT_ASSERT_ARG(author);
+
+	GIT_ERROR_CHECK_VERSION(given_opts,
+		GIT_EMAIL_CREATE_OPTIONS_VERSION,
+		"git_email_create_options");
+
+	if (given_opts)
+		memcpy(&opts, given_opts, sizeof(git_email_create_options));
+
+	git_buf_sanitize(out);
+	git_buf_clear(out);
+
+	if ((error = append_header(out, patch_idx, patch_count, commit_id, summary, author, &opts)) == 0 &&
+	    (error = append_body(out, body)) == 0 &&
+	    (error = git_buf_puts(out, "---\n")) == 0 &&
+	    (error = append_diffstat(out, diff)) == 0 &&
+	    (error = append_patches(out, diff)) == 0)
+		error = git_buf_puts(out, "--\nlibgit2 " LIBGIT2_VERSION "\n\n");
+
+	return error;
+}
+
+int git_email_create_from_diff(
+	git_buf *out,
+	git_diff *diff,
+	size_t patch_idx,
+	size_t patch_count,
+	const git_oid *commit_id,
+	const char *summary,
+	const char *body,
+	const git_signature *author,
+	const git_email_create_options *given_opts)
+{
+	int error;
+
+	git_buf_sanitize(out);
+	git_buf_clear(out);
+
+	error = git_email__append_from_diff(out, diff, patch_idx,
+		patch_count, commit_id, summary, body, author,
+		given_opts);
+
+	return error;
+}
+
+int git_email_create_from_commit(
+	git_buf *out,
+	git_commit *commit,
+	const git_email_create_options *given_opts)
+{
+	git_email_create_options opts = GIT_EMAIL_CREATE_OPTIONS_INIT;
+	git_diff *diff = NULL;
+	git_repository *repo;
+	git_diff_options *diff_opts;
+	git_diff_find_options *find_opts;
+	const git_signature *author;
+	const char *summary, *body;
+	const git_oid *commit_id;
+	int error = -1;
+
+	GIT_ASSERT_ARG(out);
+	GIT_ASSERT_ARG(commit);
+
+	GIT_ERROR_CHECK_VERSION(given_opts,
+		GIT_EMAIL_CREATE_OPTIONS_VERSION,
+		"git_email_create_options");
+
+	if (given_opts)
+		memcpy(&opts, given_opts, sizeof(git_email_create_options));
+
+	repo = git_commit_owner(commit);
+	author = git_commit_author(commit);
+	summary = git_commit_summary(commit);
+	body = git_commit_body(commit);
+	commit_id = git_commit_id(commit);
+	diff_opts = &opts.diff_opts;
+	find_opts = &opts.diff_find_opts;
+
+	if ((error = git_diff__commit(&diff, repo, commit, diff_opts)) < 0)
+		goto done;
+
+	if ((opts.flags & GIT_EMAIL_CREATE_NO_RENAMES) == 0 &&
+	    (error = git_diff_find_similar(diff, find_opts)) < 0)
+		goto done;
+
+	error = git_email_create_from_diff(out, diff, 1, 1, commit_id, summary, body, author, &opts);
+
+done:
+	git_diff_free(diff);
+	return error;
+}
diff --git a/src/email.h b/src/email.h
new file mode 100644
index 000000000..7aeb462ab
--- /dev/null
+++ b/src/email.h
@@ -0,0 +1,25 @@
+/*
+ * Copyright (C) the libgit2 contributors. All rights reserved.
+ *
+ * This file is part of libgit2, distributed under the GNU GPL v2 with
+ * a Linking Exception. For full terms see the included COPYING file.
+ */
+#ifndef INCLUDE_email_h__
+#define INCLUDE_email_h__
+
+#include "common.h"
+
+#include "git2/email.h"
+
+extern int git_email__append_from_diff(
+	git_buf *out,
+	git_diff *diff,
+	size_t patch_idx,
+	size_t patch_count,
+	const git_oid *commit_id,
+	const char *summary,
+	const char *body,
+	const git_signature *author,
+	const git_email_create_options *given_opts);
+
+#endif