From 3e20dcf367f551e5a0efab74e7bc2c07f0549a3d Mon Sep 17 00:00:00 2001 From: Paul Tan Date: Tue, 4 Aug 2015 21:51:28 +0800 Subject: [PATCH] builtin-am: extract patch and commit info with git-mailinfo For the purpose of applying the patch and committing the results, implement extracting the patch data, commit message and authorship from an e-mail message using git-mailinfo. git-mailinfo is run as a separate process, but ideally in the future, we should be be able to access its functionality directly without spawning a new process. Helped-by: Junio C Hamano Helped-by: Jeff King Helped-by: Johannes Schindelin Signed-off-by: Paul Tan Signed-off-by: Junio C Hamano --- builtin/am.c | 317 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 317 insertions(+) diff --git a/builtin/am.c b/builtin/am.c index c12566ab4a..63f0fa4dcf 100644 --- a/builtin/am.c +++ b/builtin/am.c @@ -9,6 +9,23 @@ #include "parse-options.h" #include "dir.h" #include "run-command.h" +#include "quote.h" + +/** + * Returns 1 if the file is empty or does not exist, 0 otherwise. + */ +static int is_empty_file(const char *filename) +{ + struct stat st; + + if (stat(filename, &st) < 0) { + if (errno == ENOENT) + return 1; + die_errno(_("could not stat %s"), filename); + } + + return !st.st_size; +} /** * Like strbuf_getline(), but treats both '\n' and "\r\n" as line terminators. @@ -38,6 +55,13 @@ struct am_state { int cur; int last; + /* commit metadata and message */ + char *author_name; + char *author_email; + char *author_date; + char *msg; + size_t msg_len; + /* number of digits in patch filename */ int prec; }; @@ -62,6 +86,10 @@ static void am_state_init(struct am_state *state, const char *dir) static void am_state_release(struct am_state *state) { free(state->dir); + free(state->author_name); + free(state->author_email); + free(state->author_date); + free(state->msg); } /** @@ -112,6 +140,161 @@ static int read_state_file(struct strbuf *sb, const struct am_state *state, } /** + * Reads a KEY=VALUE shell variable assignment from `fp`, returning the VALUE + * as a newly-allocated string. VALUE must be a quoted string, and the KEY must + * match `key`. Returns NULL on failure. + * + * This is used by read_author_script() to read the GIT_AUTHOR_* variables from + * the author-script. + */ +static char *read_shell_var(FILE *fp, const char *key) +{ + struct strbuf sb = STRBUF_INIT; + const char *str; + + if (strbuf_getline(&sb, fp, '\n')) + goto fail; + + if (!skip_prefix(sb.buf, key, &str)) + goto fail; + + if (!skip_prefix(str, "=", &str)) + goto fail; + + strbuf_remove(&sb, 0, str - sb.buf); + + str = sq_dequote(sb.buf); + if (!str) + goto fail; + + return strbuf_detach(&sb, NULL); + +fail: + strbuf_release(&sb); + return NULL; +} + +/** + * Reads and parses the state directory's "author-script" file, and sets + * state->author_name, state->author_email and state->author_date accordingly. + * Returns 0 on success, -1 if the file could not be parsed. + * + * The author script is of the format: + * + * GIT_AUTHOR_NAME='$author_name' + * GIT_AUTHOR_EMAIL='$author_email' + * GIT_AUTHOR_DATE='$author_date' + * + * where $author_name, $author_email and $author_date are quoted. We are strict + * with our parsing, as the file was meant to be eval'd in the old git-am.sh + * script, and thus if the file differs from what this function expects, it is + * better to bail out than to do something that the user does not expect. + */ +static int read_author_script(struct am_state *state) +{ + const char *filename = am_path(state, "author-script"); + FILE *fp; + + assert(!state->author_name); + assert(!state->author_email); + assert(!state->author_date); + + fp = fopen(filename, "r"); + if (!fp) { + if (errno == ENOENT) + return 0; + die_errno(_("could not open '%s' for reading"), filename); + } + + state->author_name = read_shell_var(fp, "GIT_AUTHOR_NAME"); + if (!state->author_name) { + fclose(fp); + return -1; + } + + state->author_email = read_shell_var(fp, "GIT_AUTHOR_EMAIL"); + if (!state->author_email) { + fclose(fp); + return -1; + } + + state->author_date = read_shell_var(fp, "GIT_AUTHOR_DATE"); + if (!state->author_date) { + fclose(fp); + return -1; + } + + if (fgetc(fp) != EOF) { + fclose(fp); + return -1; + } + + fclose(fp); + return 0; +} + +/** + * Saves state->author_name, state->author_email and state->author_date in the + * state directory's "author-script" file. + */ +static void write_author_script(const struct am_state *state) +{ + struct strbuf sb = STRBUF_INIT; + + strbuf_addstr(&sb, "GIT_AUTHOR_NAME="); + sq_quote_buf(&sb, state->author_name); + strbuf_addch(&sb, '\n'); + + strbuf_addstr(&sb, "GIT_AUTHOR_EMAIL="); + sq_quote_buf(&sb, state->author_email); + strbuf_addch(&sb, '\n'); + + strbuf_addstr(&sb, "GIT_AUTHOR_DATE="); + sq_quote_buf(&sb, state->author_date); + strbuf_addch(&sb, '\n'); + + write_file(am_path(state, "author-script"), 1, "%s", sb.buf); + + strbuf_release(&sb); +} + +/** + * Reads the commit message from the state directory's "final-commit" file, + * setting state->msg to its contents and state->msg_len to the length of its + * contents in bytes. + * + * Returns 0 on success, -1 if the file does not exist. + */ +static int read_commit_msg(struct am_state *state) +{ + struct strbuf sb = STRBUF_INIT; + + assert(!state->msg); + + if (read_state_file(&sb, state, "final-commit", 0) < 0) { + strbuf_release(&sb); + return -1; + } + + state->msg = strbuf_detach(&sb, &state->msg_len); + return 0; +} + +/** + * Saves state->msg in the state directory's "final-commit" file. + */ +static void write_commit_msg(const struct am_state *state) +{ + int fd; + const char *filename = am_path(state, "final-commit"); + + fd = xopen(filename, O_WRONLY | O_CREAT, 0666); + if (write_in_full(fd, state->msg, state->msg_len) < 0) + die_errno(_("could not write to %s"), filename); + close(fd); +} + +/** * Loads state from disk. */ static void am_load(struct am_state *state) @@ -126,6 +309,11 @@ static void am_load(struct am_state *state) die("BUG: state file 'last' does not exist"); state->last = strtol(sb.buf, NULL, 10); + if (read_author_script(state) < 0) + die(_("could not parse author script")); + + read_commit_msg(state); + strbuf_release(&sb); } @@ -318,19 +506,148 @@ static void am_setup(struct am_state *state, enum patch_format patch_format, */ static void am_next(struct am_state *state) { + free(state->author_name); + state->author_name = NULL; + + free(state->author_email); + state->author_email = NULL; + + free(state->author_date); + state->author_date = NULL; + + free(state->msg); + state->msg = NULL; + state->msg_len = 0; + + unlink(am_path(state, "author-script")); + unlink(am_path(state, "final-commit")); + state->cur++; write_file(am_path(state, "next"), 1, "%d", state->cur); } /** + * Returns the filename of the current patch email. + */ +static const char *msgnum(const struct am_state *state) +{ + static struct strbuf sb = STRBUF_INIT; + + strbuf_reset(&sb); + strbuf_addf(&sb, "%0*d", state->prec, state->cur); + + return sb.buf; +} + +/** + * Parses `mail` using git-mailinfo, extracting its patch and authorship info. + * state->msg will be set to the patch message. state->author_name, + * state->author_email and state->author_date will be set to the patch author's + * name, email and date respectively. The patch body will be written to the + * state directory's "patch" file. + * + * Returns 1 if the patch should be skipped, 0 otherwise. + */ +static int parse_mail(struct am_state *state, const char *mail) +{ + FILE *fp; + struct child_process cp = CHILD_PROCESS_INIT; + struct strbuf sb = STRBUF_INIT; + struct strbuf msg = STRBUF_INIT; + struct strbuf author_name = STRBUF_INIT; + struct strbuf author_date = STRBUF_INIT; + struct strbuf author_email = STRBUF_INIT; + int ret = 0; + + cp.git_cmd = 1; + cp.in = xopen(mail, O_RDONLY, 0); + cp.out = xopen(am_path(state, "info"), O_WRONLY | O_CREAT, 0777); + + argv_array_push(&cp.args, "mailinfo"); + argv_array_push(&cp.args, am_path(state, "msg")); + argv_array_push(&cp.args, am_path(state, "patch")); + + if (run_command(&cp) < 0) + die("could not parse patch"); + + close(cp.in); + close(cp.out); + + /* Extract message and author information */ + fp = xfopen(am_path(state, "info"), "r"); + while (!strbuf_getline(&sb, fp, '\n')) { + const char *x; + + if (skip_prefix(sb.buf, "Subject: ", &x)) { + if (msg.len) + strbuf_addch(&msg, '\n'); + strbuf_addstr(&msg, x); + } else if (skip_prefix(sb.buf, "Author: ", &x)) + strbuf_addstr(&author_name, x); + else if (skip_prefix(sb.buf, "Email: ", &x)) + strbuf_addstr(&author_email, x); + else if (skip_prefix(sb.buf, "Date: ", &x)) + strbuf_addstr(&author_date, x); + } + fclose(fp); + + /* Skip pine's internal folder data */ + if (!strcmp(author_name.buf, "Mail System Internal Data")) { + ret = 1; + goto finish; + } + + if (is_empty_file(am_path(state, "patch"))) { + printf_ln(_("Patch is empty. Was it split wrong?")); + exit(128); + } + + strbuf_addstr(&msg, "\n\n"); + if (strbuf_read_file(&msg, am_path(state, "msg"), 0) < 0) + die_errno(_("could not read '%s'"), am_path(state, "msg")); + stripspace(&msg, 0); + + assert(!state->author_name); + state->author_name = strbuf_detach(&author_name, NULL); + + assert(!state->author_email); + state->author_email = strbuf_detach(&author_email, NULL); + + assert(!state->author_date); + state->author_date = strbuf_detach(&author_date, NULL); + + assert(!state->msg); + state->msg = strbuf_detach(&msg, &state->msg_len); + +finish: + strbuf_release(&msg); + strbuf_release(&author_date); + strbuf_release(&author_email); + strbuf_release(&author_name); + strbuf_release(&sb); + return ret; +} + +/** * Applies all queued mail. */ static void am_run(struct am_state *state) { while (state->cur <= state->last) { + const char *mail = am_path(state, msgnum(state)); + + if (!file_exists(mail)) + goto next; + + if (parse_mail(state, mail)) + goto next; /* mail should be skipped */ + + write_author_script(state); + write_commit_msg(state); /* NEEDSWORK: Patch application not implemented yet */ +next: am_next(state); } -- 2.11.4.GIT