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-rw-r--r--trailer.c873
1 files changed, 873 insertions, 0 deletions
diff --git a/trailer.c b/trailer.c
new file mode 100644
index 0000000000..05b3859b47
--- /dev/null
+++ b/trailer.c
@@ -0,0 +1,873 @@
+#include "cache.h"
+#include "string-list.h"
+#include "run-command.h"
+#include "commit.h"
+#include "trailer.h"
+/*
+ * Copyright (c) 2013, 2014 Christian Couder <chriscool@tuxfamily.org>
+ */
+
+enum action_where { WHERE_END, WHERE_AFTER, WHERE_BEFORE, WHERE_START };
+enum action_if_exists { EXISTS_ADD_IF_DIFFERENT_NEIGHBOR, EXISTS_ADD_IF_DIFFERENT,
+ EXISTS_ADD, EXISTS_REPLACE, EXISTS_DO_NOTHING };
+enum action_if_missing { MISSING_ADD, MISSING_DO_NOTHING };
+
+struct conf_info {
+ char *name;
+ char *key;
+ char *command;
+ enum action_where where;
+ enum action_if_exists if_exists;
+ enum action_if_missing if_missing;
+};
+
+static struct conf_info default_conf_info;
+
+struct trailer_item {
+ struct trailer_item *previous;
+ struct trailer_item *next;
+ const char *token;
+ const char *value;
+ struct conf_info conf;
+};
+
+static struct trailer_item *first_conf_item;
+
+static char *separators = ":";
+
+#define TRAILER_ARG_STRING "$ARG"
+
+static int after_or_end(enum action_where where)
+{
+ return (where == WHERE_AFTER) || (where == WHERE_END);
+}
+
+/*
+ * Return the length of the string not including any final
+ * punctuation. E.g., the input "Signed-off-by:" would return
+ * 13, stripping the trailing punctuation but retaining
+ * internal punctuation.
+ */
+static size_t token_len_without_separator(const char *token, size_t len)
+{
+ while (len > 0 && !isalnum(token[len - 1]))
+ len--;
+ return len;
+}
+
+static int same_token(struct trailer_item *a, struct trailer_item *b)
+{
+ size_t a_len = token_len_without_separator(a->token, strlen(a->token));
+ size_t b_len = token_len_without_separator(b->token, strlen(b->token));
+ size_t min_len = (a_len > b_len) ? b_len : a_len;
+
+ return !strncasecmp(a->token, b->token, min_len);
+}
+
+static int same_value(struct trailer_item *a, struct trailer_item *b)
+{
+ return !strcasecmp(a->value, b->value);
+}
+
+static int same_trailer(struct trailer_item *a, struct trailer_item *b)
+{
+ return same_token(a, b) && same_value(a, b);
+}
+
+static inline int contains_only_spaces(const char *str)
+{
+ const char *s = str;
+ while (*s && isspace(*s))
+ s++;
+ return !*s;
+}
+
+static inline void strbuf_replace(struct strbuf *sb, const char *a, const char *b)
+{
+ const char *ptr = strstr(sb->buf, a);
+ if (ptr)
+ strbuf_splice(sb, ptr - sb->buf, strlen(a), b, strlen(b));
+}
+
+static void free_trailer_item(struct trailer_item *item)
+{
+ free(item->conf.name);
+ free(item->conf.key);
+ free(item->conf.command);
+ free((char *)item->token);
+ free((char *)item->value);
+ free(item);
+}
+
+static char last_non_space_char(const char *s)
+{
+ int i;
+ for (i = strlen(s) - 1; i >= 0; i--)
+ if (!isspace(s[i]))
+ return s[i];
+ return '\0';
+}
+
+static void print_tok_val(const char *tok, const char *val)
+{
+ char c = last_non_space_char(tok);
+ if (!c)
+ return;
+ if (strchr(separators, c))
+ printf("%s%s\n", tok, val);
+ else
+ printf("%s%c %s\n", tok, separators[0], val);
+}
+
+static void print_all(struct trailer_item *first, int trim_empty)
+{
+ struct trailer_item *item;
+ for (item = first; item; item = item->next) {
+ if (!trim_empty || strlen(item->value) > 0)
+ print_tok_val(item->token, item->value);
+ }
+}
+
+static void update_last(struct trailer_item **last)
+{
+ if (*last)
+ while ((*last)->next != NULL)
+ *last = (*last)->next;
+}
+
+static void update_first(struct trailer_item **first)
+{
+ if (*first)
+ while ((*first)->previous != NULL)
+ *first = (*first)->previous;
+}
+
+static void add_arg_to_input_list(struct trailer_item *on_tok,
+ struct trailer_item *arg_tok,
+ struct trailer_item **first,
+ struct trailer_item **last)
+{
+ if (after_or_end(arg_tok->conf.where)) {
+ arg_tok->next = on_tok->next;
+ on_tok->next = arg_tok;
+ arg_tok->previous = on_tok;
+ if (arg_tok->next)
+ arg_tok->next->previous = arg_tok;
+ update_last(last);
+ } else {
+ arg_tok->previous = on_tok->previous;
+ on_tok->previous = arg_tok;
+ arg_tok->next = on_tok;
+ if (arg_tok->previous)
+ arg_tok->previous->next = arg_tok;
+ update_first(first);
+ }
+}
+
+static int check_if_different(struct trailer_item *in_tok,
+ struct trailer_item *arg_tok,
+ int check_all)
+{
+ enum action_where where = arg_tok->conf.where;
+ do {
+ if (!in_tok)
+ return 1;
+ if (same_trailer(in_tok, arg_tok))
+ return 0;
+ /*
+ * if we want to add a trailer after another one,
+ * we have to check those before this one
+ */
+ in_tok = after_or_end(where) ? in_tok->previous : in_tok->next;
+ } while (check_all);
+ return 1;
+}
+
+static void remove_from_list(struct trailer_item *item,
+ struct trailer_item **first,
+ struct trailer_item **last)
+{
+ struct trailer_item *next = item->next;
+ struct trailer_item *previous = item->previous;
+
+ if (next) {
+ item->next->previous = previous;
+ item->next = NULL;
+ } else if (last)
+ *last = previous;
+
+ if (previous) {
+ item->previous->next = next;
+ item->previous = NULL;
+ } else if (first)
+ *first = next;
+}
+
+static struct trailer_item *remove_first(struct trailer_item **first)
+{
+ struct trailer_item *item = *first;
+ *first = item->next;
+ if (item->next) {
+ item->next->previous = NULL;
+ item->next = NULL;
+ }
+ return item;
+}
+
+static int read_from_command(struct child_process *cp, struct strbuf *buf)
+{
+ if (run_command(cp))
+ return error("running trailer command '%s' failed", cp->argv[0]);
+ if (strbuf_read(buf, cp->out, 1024) < 1)
+ return error("reading from trailer command '%s' failed", cp->argv[0]);
+ strbuf_trim(buf);
+ return 0;
+}
+
+static const char *apply_command(const char *command, const char *arg)
+{
+ struct strbuf cmd = STRBUF_INIT;
+ struct strbuf buf = STRBUF_INIT;
+ struct child_process cp = CHILD_PROCESS_INIT;
+ const char *argv[] = {NULL, NULL};
+ const char *result;
+
+ strbuf_addstr(&cmd, command);
+ if (arg)
+ strbuf_replace(&cmd, TRAILER_ARG_STRING, arg);
+
+ argv[0] = cmd.buf;
+ cp.argv = argv;
+ cp.env = local_repo_env;
+ cp.no_stdin = 1;
+ cp.out = -1;
+ cp.use_shell = 1;
+
+ if (read_from_command(&cp, &buf)) {
+ strbuf_release(&buf);
+ result = xstrdup("");
+ } else
+ result = strbuf_detach(&buf, NULL);
+
+ strbuf_release(&cmd);
+ return result;
+}
+
+static void apply_item_command(struct trailer_item *in_tok, struct trailer_item *arg_tok)
+{
+ if (arg_tok->conf.command) {
+ const char *arg;
+ if (arg_tok->value && arg_tok->value[0]) {
+ arg = arg_tok->value;
+ } else {
+ if (in_tok && in_tok->value)
+ arg = xstrdup(in_tok->value);
+ else
+ arg = xstrdup("");
+ }
+ arg_tok->value = apply_command(arg_tok->conf.command, arg);
+ free((char *)arg);
+ }
+}
+
+static void apply_arg_if_exists(struct trailer_item *in_tok,
+ struct trailer_item *arg_tok,
+ struct trailer_item *on_tok,
+ struct trailer_item **in_tok_first,
+ struct trailer_item **in_tok_last)
+{
+ switch (arg_tok->conf.if_exists) {
+ case EXISTS_DO_NOTHING:
+ free_trailer_item(arg_tok);
+ break;
+ case EXISTS_REPLACE:
+ apply_item_command(in_tok, arg_tok);
+ add_arg_to_input_list(on_tok, arg_tok,
+ in_tok_first, in_tok_last);
+ remove_from_list(in_tok, in_tok_first, in_tok_last);
+ free_trailer_item(in_tok);
+ break;
+ case EXISTS_ADD:
+ apply_item_command(in_tok, arg_tok);
+ add_arg_to_input_list(on_tok, arg_tok,
+ in_tok_first, in_tok_last);
+ break;
+ case EXISTS_ADD_IF_DIFFERENT:
+ apply_item_command(in_tok, arg_tok);
+ if (check_if_different(in_tok, arg_tok, 1))
+ add_arg_to_input_list(on_tok, arg_tok,
+ in_tok_first, in_tok_last);
+ else
+ free_trailer_item(arg_tok);
+ break;
+ case EXISTS_ADD_IF_DIFFERENT_NEIGHBOR:
+ apply_item_command(in_tok, arg_tok);
+ if (check_if_different(on_tok, arg_tok, 0))
+ add_arg_to_input_list(on_tok, arg_tok,
+ in_tok_first, in_tok_last);
+ else
+ free_trailer_item(arg_tok);
+ break;
+ }
+}
+
+static void apply_arg_if_missing(struct trailer_item **in_tok_first,
+ struct trailer_item **in_tok_last,
+ struct trailer_item *arg_tok)
+{
+ struct trailer_item **in_tok;
+ enum action_where where;
+
+ switch (arg_tok->conf.if_missing) {
+ case MISSING_DO_NOTHING:
+ free_trailer_item(arg_tok);
+ break;
+ case MISSING_ADD:
+ where = arg_tok->conf.where;
+ in_tok = after_or_end(where) ? in_tok_last : in_tok_first;
+ apply_item_command(NULL, arg_tok);
+ if (*in_tok) {
+ add_arg_to_input_list(*in_tok, arg_tok,
+ in_tok_first, in_tok_last);
+ } else {
+ *in_tok_first = arg_tok;
+ *in_tok_last = arg_tok;
+ }
+ break;
+ }
+}
+
+static int find_same_and_apply_arg(struct trailer_item **in_tok_first,
+ struct trailer_item **in_tok_last,
+ struct trailer_item *arg_tok)
+{
+ struct trailer_item *in_tok;
+ struct trailer_item *on_tok;
+ struct trailer_item *following_tok;
+
+ enum action_where where = arg_tok->conf.where;
+ int middle = (where == WHERE_AFTER) || (where == WHERE_BEFORE);
+ int backwards = after_or_end(where);
+ struct trailer_item *start_tok = backwards ? *in_tok_last : *in_tok_first;
+
+ for (in_tok = start_tok; in_tok; in_tok = following_tok) {
+ following_tok = backwards ? in_tok->previous : in_tok->next;
+ if (!same_token(in_tok, arg_tok))
+ continue;
+ on_tok = middle ? in_tok : start_tok;
+ apply_arg_if_exists(in_tok, arg_tok, on_tok,
+ in_tok_first, in_tok_last);
+ return 1;
+ }
+ return 0;
+}
+
+static void process_trailers_lists(struct trailer_item **in_tok_first,
+ struct trailer_item **in_tok_last,
+ struct trailer_item **arg_tok_first)
+{
+ struct trailer_item *arg_tok;
+ struct trailer_item *next_arg;
+
+ if (!*arg_tok_first)
+ return;
+
+ for (arg_tok = *arg_tok_first; arg_tok; arg_tok = next_arg) {
+ int applied = 0;
+
+ next_arg = arg_tok->next;
+ remove_from_list(arg_tok, arg_tok_first, NULL);
+
+ applied = find_same_and_apply_arg(in_tok_first,
+ in_tok_last,
+ arg_tok);
+
+ if (!applied)
+ apply_arg_if_missing(in_tok_first,
+ in_tok_last,
+ arg_tok);
+ }
+}
+
+static int set_where(struct conf_info *item, const char *value)
+{
+ if (!strcasecmp("after", value))
+ item->where = WHERE_AFTER;
+ else if (!strcasecmp("before", value))
+ item->where = WHERE_BEFORE;
+ else if (!strcasecmp("end", value))
+ item->where = WHERE_END;
+ else if (!strcasecmp("start", value))
+ item->where = WHERE_START;
+ else
+ return -1;
+ return 0;
+}
+
+static int set_if_exists(struct conf_info *item, const char *value)
+{
+ if (!strcasecmp("addIfDifferent", value))
+ item->if_exists = EXISTS_ADD_IF_DIFFERENT;
+ else if (!strcasecmp("addIfDifferentNeighbor", value))
+ item->if_exists = EXISTS_ADD_IF_DIFFERENT_NEIGHBOR;
+ else if (!strcasecmp("add", value))
+ item->if_exists = EXISTS_ADD;
+ else if (!strcasecmp("replace", value))
+ item->if_exists = EXISTS_REPLACE;
+ else if (!strcasecmp("doNothing", value))
+ item->if_exists = EXISTS_DO_NOTHING;
+ else
+ return -1;
+ return 0;
+}
+
+static int set_if_missing(struct conf_info *item, const char *value)
+{
+ if (!strcasecmp("doNothing", value))
+ item->if_missing = MISSING_DO_NOTHING;
+ else if (!strcasecmp("add", value))
+ item->if_missing = MISSING_ADD;
+ else
+ return -1;
+ return 0;
+}
+
+static void duplicate_conf(struct conf_info *dst, struct conf_info *src)
+{
+ *dst = *src;
+ if (src->name)
+ dst->name = xstrdup(src->name);
+ if (src->key)
+ dst->key = xstrdup(src->key);
+ if (src->command)
+ dst->command = xstrdup(src->command);
+}
+
+static struct trailer_item *get_conf_item(const char *name)
+{
+ struct trailer_item *item;
+ struct trailer_item *previous;
+
+ /* Look up item with same name */
+ for (previous = NULL, item = first_conf_item;
+ item;
+ previous = item, item = item->next) {
+ if (!strcasecmp(item->conf.name, name))
+ return item;
+ }
+
+ /* Item does not already exists, create it */
+ item = xcalloc(sizeof(struct trailer_item), 1);
+ duplicate_conf(&item->conf, &default_conf_info);
+ item->conf.name = xstrdup(name);
+
+ if (!previous)
+ first_conf_item = item;
+ else {
+ previous->next = item;
+ item->previous = previous;
+ }
+
+ return item;
+}
+
+enum trailer_info_type { TRAILER_KEY, TRAILER_COMMAND, TRAILER_WHERE,
+ TRAILER_IF_EXISTS, TRAILER_IF_MISSING };
+
+static struct {
+ const char *name;
+ enum trailer_info_type type;
+} trailer_config_items[] = {
+ { "key", TRAILER_KEY },
+ { "command", TRAILER_COMMAND },
+ { "where", TRAILER_WHERE },
+ { "ifexists", TRAILER_IF_EXISTS },
+ { "ifmissing", TRAILER_IF_MISSING }
+};
+
+static int git_trailer_default_config(const char *conf_key, const char *value, void *cb)
+{
+ const char *trailer_item, *variable_name;
+
+ if (!skip_prefix(conf_key, "trailer.", &trailer_item))
+ return 0;
+
+ variable_name = strrchr(trailer_item, '.');
+ if (!variable_name) {
+ if (!strcmp(trailer_item, "where")) {
+ if (set_where(&default_conf_info, value) < 0)
+ warning(_("unknown value '%s' for key '%s'"),
+ value, conf_key);
+ } else if (!strcmp(trailer_item, "ifexists")) {
+ if (set_if_exists(&default_conf_info, value) < 0)
+ warning(_("unknown value '%s' for key '%s'"),
+ value, conf_key);
+ } else if (!strcmp(trailer_item, "ifmissing")) {
+ if (set_if_missing(&default_conf_info, value) < 0)
+ warning(_("unknown value '%s' for key '%s'"),
+ value, conf_key);
+ } else if (!strcmp(trailer_item, "separators")) {
+ separators = xstrdup(value);
+ }
+ }
+ return 0;
+}
+
+static int git_trailer_config(const char *conf_key, const char *value, void *cb)
+{
+ const char *trailer_item, *variable_name;
+ struct trailer_item *item;
+ struct conf_info *conf;
+ char *name = NULL;
+ enum trailer_info_type type;
+ int i;
+
+ if (!skip_prefix(conf_key, "trailer.", &trailer_item))
+ return 0;
+
+ variable_name = strrchr(trailer_item, '.');
+ if (!variable_name)
+ return 0;
+
+ variable_name++;
+ for (i = 0; i < ARRAY_SIZE(trailer_config_items); i++) {
+ if (strcmp(trailer_config_items[i].name, variable_name))
+ continue;
+ name = xstrndup(trailer_item, variable_name - trailer_item - 1);
+ type = trailer_config_items[i].type;
+ break;
+ }
+
+ if (!name)
+ return 0;
+
+ item = get_conf_item(name);
+ conf = &item->conf;
+ free(name);
+
+ switch (type) {
+ case TRAILER_KEY:
+ if (conf->key)
+ warning(_("more than one %s"), conf_key);
+ conf->key = xstrdup(value);
+ break;
+ case TRAILER_COMMAND:
+ if (conf->command)
+ warning(_("more than one %s"), conf_key);
+ conf->command = xstrdup(value);
+ break;
+ case TRAILER_WHERE:
+ if (set_where(conf, value))
+ warning(_("unknown value '%s' for key '%s'"), value, conf_key);
+ break;
+ case TRAILER_IF_EXISTS:
+ if (set_if_exists(conf, value))
+ warning(_("unknown value '%s' for key '%s'"), value, conf_key);
+ break;
+ case TRAILER_IF_MISSING:
+ if (set_if_missing(conf, value))
+ warning(_("unknown value '%s' for key '%s'"), value, conf_key);
+ break;
+ default:
+ die("internal bug in trailer.c");
+ }
+ return 0;
+}
+
+static int parse_trailer(struct strbuf *tok, struct strbuf *val, const char *trailer)
+{
+ size_t len;
+ struct strbuf seps = STRBUF_INIT;
+ strbuf_addstr(&seps, separators);
+ strbuf_addch(&seps, '=');
+ len = strcspn(trailer, seps.buf);
+ strbuf_release(&seps);
+ if (len == 0) {
+ int l = strlen(trailer);
+ while (l > 0 && isspace(trailer[l - 1]))
+ l--;
+ return error(_("empty trailer token in trailer '%.*s'"), l, trailer);
+ }
+ if (len < strlen(trailer)) {
+ strbuf_add(tok, trailer, len);
+ strbuf_trim(tok);
+ strbuf_addstr(val, trailer + len + 1);
+ strbuf_trim(val);
+ } else {
+ strbuf_addstr(tok, trailer);
+ strbuf_trim(tok);
+ }
+ return 0;
+}
+
+static const char *token_from_item(struct trailer_item *item, char *tok)
+{
+ if (item->conf.key)
+ return item->conf.key;
+ if (tok)
+ return tok;
+ return item->conf.name;
+}
+
+static struct trailer_item *new_trailer_item(struct trailer_item *conf_item,
+ char *tok, char *val)
+{
+ struct trailer_item *new = xcalloc(sizeof(*new), 1);
+ new->value = val ? val : xstrdup("");
+
+ if (conf_item) {
+ duplicate_conf(&new->conf, &conf_item->conf);
+ new->token = xstrdup(token_from_item(conf_item, tok));
+ free(tok);
+ } else {
+ duplicate_conf(&new->conf, &default_conf_info);
+ new->token = tok;
+ }
+
+ return new;
+}
+
+static int token_matches_item(const char *tok, struct trailer_item *item, int tok_len)
+{
+ if (!strncasecmp(tok, item->conf.name, tok_len))
+ return 1;
+ return item->conf.key ? !strncasecmp(tok, item->conf.key, tok_len) : 0;
+}
+
+static struct trailer_item *create_trailer_item(const char *string)
+{
+ struct strbuf tok = STRBUF_INIT;
+ struct strbuf val = STRBUF_INIT;
+ struct trailer_item *item;
+ int tok_len;
+
+ if (parse_trailer(&tok, &val, string))
+ return NULL;
+
+ tok_len = token_len_without_separator(tok.buf, tok.len);
+
+ /* Lookup if the token matches something in the config */
+ for (item = first_conf_item; item; item = item->next) {
+ if (token_matches_item(tok.buf, item, tok_len))
+ return new_trailer_item(item,
+ strbuf_detach(&tok, NULL),
+ strbuf_detach(&val, NULL));
+ }
+
+ return new_trailer_item(NULL,
+ strbuf_detach(&tok, NULL),
+ strbuf_detach(&val, NULL));
+}
+
+static void add_trailer_item(struct trailer_item **first,
+ struct trailer_item **last,
+ struct trailer_item *new)
+{
+ if (!new)
+ return;
+ if (!*last) {
+ *first = new;
+ *last = new;
+ } else {
+ (*last)->next = new;
+ new->previous = *last;
+ *last = new;
+ }
+}
+
+static struct trailer_item *process_command_line_args(struct string_list *trailers)
+{
+ struct trailer_item *arg_tok_first = NULL;
+ struct trailer_item *arg_tok_last = NULL;
+ struct string_list_item *tr;
+ struct trailer_item *item;
+
+ /* Add a trailer item for each configured trailer with a command */
+ for (item = first_conf_item; item; item = item->next) {
+ if (item->conf.command) {
+ struct trailer_item *new = new_trailer_item(item, NULL, NULL);
+ add_trailer_item(&arg_tok_first, &arg_tok_last, new);
+ }
+ }
+
+ /* Add a trailer item for each trailer on the command line */
+ for_each_string_list_item(tr, trailers) {
+ struct trailer_item *new = create_trailer_item(tr->string);
+ add_trailer_item(&arg_tok_first, &arg_tok_last, new);
+ }
+
+ return arg_tok_first;
+}
+
+static struct strbuf **read_input_file(const char *file)
+{
+ struct strbuf **lines;
+ struct strbuf sb = STRBUF_INIT;
+
+ if (file) {
+ if (strbuf_read_file(&sb, file, 0) < 0)
+ die_errno(_("could not read input file '%s'"), file);
+ } else {
+ if (strbuf_read(&sb, fileno(stdin), 0) < 0)
+ die_errno(_("could not read from stdin"));
+ }
+
+ lines = strbuf_split(&sb, '\n');
+
+ strbuf_release(&sb);
+
+ return lines;
+}
+
+/*
+ * Return the (0 based) index of the start of the patch or the line
+ * count if there is no patch in the message.
+ */
+static int find_patch_start(struct strbuf **lines, int count)
+{
+ int i;
+
+ /* Get the start of the patch part if any */
+ for (i = 0; i < count; i++) {
+ if (starts_with(lines[i]->buf, "---"))
+ return i;
+ }
+
+ return count;
+}
+
+/*
+ * Return the (0 based) index of the first trailer line or count if
+ * there are no trailers. Trailers are searched only in the lines from
+ * index (count - 1) down to index 0.
+ */
+static int find_trailer_start(struct strbuf **lines, int count)
+{
+ int start, only_spaces = 1;
+
+ /*
+ * Get the start of the trailers by looking starting from the end
+ * for a line with only spaces before lines with one separator.
+ */
+ for (start = count - 1; start >= 0; start--) {
+ if (lines[start]->buf[0] == comment_line_char)
+ continue;
+ if (contains_only_spaces(lines[start]->buf)) {
+ if (only_spaces)
+ continue;
+ return start + 1;
+ }
+ if (strcspn(lines[start]->buf, separators) < lines[start]->len) {
+ if (only_spaces)
+ only_spaces = 0;
+ continue;
+ }
+ return count;
+ }
+
+ return only_spaces ? count : 0;
+}
+
+/* Get the index of the end of the trailers */
+static int find_trailer_end(struct strbuf **lines, int patch_start)
+{
+ struct strbuf sb = STRBUF_INIT;
+ int i, ignore_bytes;
+
+ for (i = 0; i < patch_start; i++)
+ strbuf_addbuf(&sb, lines[i]);
+ ignore_bytes = ignore_non_trailer(&sb);
+ strbuf_release(&sb);
+ for (i = patch_start - 1; i >= 0 && ignore_bytes > 0; i--)
+ ignore_bytes -= lines[i]->len;
+
+ return i + 1;
+}
+
+static int has_blank_line_before(struct strbuf **lines, int start)
+{
+ for (;start >= 0; start--) {
+ if (lines[start]->buf[0] == comment_line_char)
+ continue;
+ return contains_only_spaces(lines[start]->buf);
+ }
+ return 0;
+}
+
+static void print_lines(struct strbuf **lines, int start, int end)
+{
+ int i;
+ for (i = start; lines[i] && i < end; i++)
+ printf("%s", lines[i]->buf);
+}
+
+static int process_input_file(struct strbuf **lines,
+ struct trailer_item **in_tok_first,
+ struct trailer_item **in_tok_last)
+{
+ int count = 0;
+ int patch_start, trailer_start, trailer_end, i;
+
+ /* Get the line count */
+ while (lines[count])
+ count++;
+
+ patch_start = find_patch_start(lines, count);
+ trailer_end = find_trailer_end(lines, patch_start);
+ trailer_start = find_trailer_start(lines, trailer_end);
+
+ /* Print lines before the trailers as is */
+ print_lines(lines, 0, trailer_start);
+
+ if (!has_blank_line_before(lines, trailer_start - 1))
+ printf("\n");
+
+ /* Parse trailer lines */
+ for (i = trailer_start; i < trailer_end; i++) {
+ if (lines[i]->buf[0] != comment_line_char) {
+ struct trailer_item *new = create_trailer_item(lines[i]->buf);
+ add_trailer_item(in_tok_first, in_tok_last, new);
+ }
+ }
+
+ return trailer_end;
+}
+
+static void free_all(struct trailer_item **first)
+{
+ while (*first) {
+ struct trailer_item *item = remove_first(first);
+ free_trailer_item(item);
+ }
+}
+
+void process_trailers(const char *file, int trim_empty, struct string_list *trailers)
+{
+ struct trailer_item *in_tok_first = NULL;
+ struct trailer_item *in_tok_last = NULL;
+ struct trailer_item *arg_tok_first;
+ struct strbuf **lines;
+ int trailer_end;
+
+ /* Default config must be setup first */
+ git_config(git_trailer_default_config, NULL);
+ git_config(git_trailer_config, NULL);
+
+ lines = read_input_file(file);
+
+ /* Print the lines before the trailers */
+ trailer_end = process_input_file(lines, &in_tok_first, &in_tok_last);
+
+ arg_tok_first = process_command_line_args(trailers);
+
+ process_trailers_lists(&in_tok_first, &in_tok_last, &arg_tok_first);
+
+ print_all(in_tok_first, trim_empty);
+
+ free_all(&in_tok_first);
+
+ /* Print the lines after the trailers as is */
+ print_lines(lines, trailer_end, INT_MAX);
+
+ strbuf_list_free(lines);
+}