[RFC/PATCH 16/18] revert: implement parsing TODO and DONE files
- From
Christian Couder <chriscool@tuxfamily.org>
- Date
- Nov 25, 2010, 21:20 UTC
- Message-ID
- <20101125212050.5188.64875.chriscool@tuxfamily.org>
- In-Reply-To
- <20101125210138.5188.13115.chriscool@tuxfamily.org>
From: Stephan Beyer <s-beyer@gmx.net>
The code from this patch comes from the git sequencer Google Summer of Code 2008 project available here:
http://repo.or.cz/w/git/sbeyer.git
Signed-off-by: Christian Couder <chriscool@tuxfamily.org> --- builtin/revert.c | 228 ++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 files changed, 228 insertions(+), 0 deletions(-)
diff --git a/builtin/revert.c b/builtin/revert.c index fee2e38..ca65b92 100644 --- a/builtin/revert.c +++ b/builtin/revert.c @@ -70,6 +70,234 @@ static const char * const *revert_or_cherry_pick_usage(struct args_info *info) return info->action == REVERT ? revert_usage : cherry_pick_usage; } +/* + * A structure for a parsed instruction line plus a next pointer + * to allow linked list behavior + */ +struct parsed_insn { + int argc; + const char **argv; + int line; + struct strbuf orig; + struct parsed_insn *next; +}; + +struct parsed_file { + size_t count; + size_t total; + struct parsed_insn *first; + struct parsed_insn *last; + struct parsed_insn *cur; /* a versatile helper */ +}; + +static int parse_line(char *buf, size_t len, int lineno, + struct parsed_insn **line) +{ + static int alloc = 0; + static struct strbuf arg_sb = STRBUF_INIT; + static enum { + ST_START, + ST_DELIMITER, + ST_ARGUMENT, + ST_ESCAPE, + ST_DOUBLE_QUOTES, + ST_DOUBLE_QUOTES_ESCAPE, + ST_SINGLE_QUOTES, + } state = ST_START; + /* The current rules are as follows: + * 1. whitespace at the beginning is ignored + * 2. insn is everything up to next whitespace or EOL + * 3. now whitespace acts as delimiter for arguments, + * except if written in single or double quotes + * 4. \ acts as escape inside and outside double quotes. + * Inside double quotes, this is only useful for \". + * Outside, it is useful for \', \", \\ and \ . + * 5. single quotes do not have an escape character + * 6. abort on "#" (comments) + */ + + size_t i, j = 0; + struct parsed_insn *ret = *line; + + for (i = 0; i <= len; ++i) { + switch (state) { + case ST_START: + switch (buf[i]) { + case ' ': + case '\t': + continue; + case 0: + case '#': + break; + case '\'': + j = i+1; + state = ST_SINGLE_QUOTES; + break; + case '"': + j = i+1; + state = ST_DOUBLE_QUOTES; + break; + default: + j = i; + state = ST_ARGUMENT; + break; + } + /* prepare everything */ + ret = xcalloc(1, sizeof(*ret)); + ret->line = lineno; + strbuf_init(&ret->orig, len+2); + if (!buf[i] || buf[i] == '#') /* empty/comment */ + goto finish; + break; + case ST_DELIMITER: + switch (buf[i]) { + case ' ': + case '\t': + continue; + case 0: + break; + case '\'': + j = i+1; + state = ST_SINGLE_QUOTES; + break; + case '"': + j = i+1; + state = ST_DOUBLE_QUOTES; + break; + default: + j = i; + state = ST_ARGUMENT; + if (buf[i] == '#') /* a comment */ + goto finish; + break; + } + /* prepare next argument */ + ALLOC_GROW(ret->argv, ret->argc + 1, alloc); + ret->argv[ret->argc++] = strbuf_detach(&arg_sb, NULL); + break; + case ST_ARGUMENT: + switch (buf[i]) { + case ' ': + case '\t': + strbuf_add(&arg_sb, buf+j, i-j); + state = ST_DELIMITER; + break; + case '"': + strbuf_add(&arg_sb, buf+j, i-j); + j = i + 1; + state = ST_DOUBLE_QUOTES; + break; + case '\'': + strbuf_add(&arg_sb, buf+j, i-j); + j = i + 1; + state = ST_SINGLE_QUOTES; + break; + case '\\': + strbuf_add(&arg_sb, buf+j, i-j); + j = i + 1; + state = ST_ESCAPE; + default: + break; + } + break; + case ST_ESCAPE: + state = ST_ARGUMENT; + break; + case ST_DOUBLE_QUOTES: + switch (buf[i]) { + case '"': + strbuf_add(&arg_sb, buf+j, i-j); + j = i + 1; + state = ST_ARGUMENT; + break; + case '\\': + strbuf_add(&arg_sb, buf+j, i-j); + j = i + 1; + state = ST_DOUBLE_QUOTES_ESCAPE; + break; + default: + break; + } + break; + case ST_DOUBLE_QUOTES_ESCAPE: + state = ST_DOUBLE_QUOTES; + break; + case ST_SINGLE_QUOTES: + switch (buf[i]) { + case '\'': + strbuf_add(&arg_sb, buf+j, i-j); + j = i + 1; + state = ST_ARGUMENT; + break; + default: + break; + } + break; + } + } +finish: + *line = ret; + switch(state) { + case ST_DOUBLE_QUOTES: + case ST_DOUBLE_QUOTES_ESCAPE: + case ST_SINGLE_QUOTES: + strbuf_add(&arg_sb, buf+j, i-j-1); + strbuf_add(&arg_sb, "\n", 1); + return 1; + case ST_ARGUMENT: + if (i-j > 1) + strbuf_add(&arg_sb, buf+j, i-j-1); + ALLOC_GROW(ret->argv, ret->argc + 1, alloc); + ret->argv[ret->argc++] = strbuf_detach(&arg_sb, NULL); + case ST_DELIMITER: + state = ST_START; + alloc = 0; + default: + strbuf_addstr(&ret->orig, buf); + strbuf_addch(&ret->orig, '\n'); + return 0; + } +} + +static void add_parsed_line_to_parsed_file(struct parsed_insn *parsed_line, + struct parsed_file *contents) +{ + if (!contents->first) { + contents->first = parsed_line; + contents->last = parsed_line; + } else { + contents->last->next = parsed_line; + contents->last = parsed_line; + } + if (parsed_line->argv) + contents->total++; +} + +/* Parse a file fp; write result into contents */ +static void parse_file(const char *filename, struct parsed_file *contents) +{ + struct strbuf str = STRBUF_INIT; + struct parsed_insn *parsed_line = NULL; + int r = 0; + int lineno = 0; + FILE *fp = fp = fopen(filename, "r"); + if (!fp) + die_errno("Could not open file '%s'", filename); + + memset(contents, 0, sizeof(*contents)); + + while (strbuf_getline(&str, fp, '\n') != EOF) { + lineno++; + r = parse_line(str.buf, str.len, lineno, &parsed_line); + if (!r) + add_parsed_line_to_parsed_file(parsed_line, contents); + } + strbuf_release(&str); + fclose(fp); + if (r) + die("Unexpected end of file."); +} + static void parse_args(int argc, const char **argv, struct args_info *info) { int noop;
-- 1.7.3.2.504.g59d466