[GSOC][RFC] ref-filter: add contents:raw atom

Documentation/git-for-each-ref.txt

@@ -235,11 +235,12 @@ and `date` to extract the named component.  For email fields (`authoremail`,
 without angle brackets, and `:localpart` to get the part before the `@` symbol
 out of the trimmed email.
 
-The message in a commit or a tag object is `contents`, from which
-`contents:<part>` can be used to extract various parts out of:
+The data in a object is `contents`, from which `contents:<part>` can be used
+to extract various parts out of:
 
 contents:size::
-	The size in bytes of the commit or tag message.
+	The size in bytes of the commit or tag message, and the raw object size
+	of the blob or tree.
 
 contents:subject::
 	The first paragraph of the message, which typically is a
@@ -257,7 +258,17 @@ contents:signature::
 	The optional GPG signature of the tag.
 
 contents:lines=N::
-	The first `N` lines of the message.
+	The first `N` lines of the message of the commit or tag message.
+
+contents:raw::
+	The raw data of the object. For blob and tree, it priont all object data,
+	its output is equivalent to `%(contents)`; For commit and tag, it not only
+	print objects’ messages (as `%(contents)` does), but also print objects
+	headers, like the "tree XXX", "parent YYY", etc lines in commits, and the
+	"object OOO", "type TTT", etc lines in tags.
+
+Note: blob and tree objects only support `%(contents)`, `%(contents:raw)` and
+`%(contents:size)`.
 
 Additionally, the trailers as interpreted by linkgit:git-interpret-trailers[1]
 are obtained as `trailers[:options]` (or by using the historical alias

quote.c

@@ -43,6 +43,39 @@ void sq_quote_buf(struct strbuf *dst, const char *src)
 	free(to_free);
 }
 
+void sq_quote_buf_with_size(struct strbuf *dst, const char *src, size_t size)
+{
+	char *to_free = NULL;
+	size_t cur_size = 0;
+
+	if (dst->buf == src)
+		to_free = strbuf_detach(dst, NULL);
+
+	strbuf_addch(dst, '\'');
+	while (cur_size < size) {
+		size_t len = strcspn(src, "'!");
+		if (!len) {
+			strbuf_add(dst, src, 1);
+			src++;
+			cur_size++;
+		} else {
+			strbuf_add(dst, src, len);
+			src += len;
+			cur_size += len;
+		}
+		if (cur_size >= size)
+			break;
+		while (need_bs_quote(*src)) {
+			strbuf_addstr(dst, "'\\");
+			strbuf_addch(dst, *src++);
+			cur_size++;
+			strbuf_addch(dst, '\'');
+		}
+	}
+	strbuf_addch(dst, '\'');
+	free(to_free);
+}
+
 void sq_quote_buf_pretty(struct strbuf *dst, const char *src)
 {
 	static const char ok_punct[] = "+,-./:=@_^";
@@ -471,6 +504,25 @@ void perl_quote_buf(struct strbuf *sb, const char *src)
 	strbuf_addch(sb, sq);
 }
 
+void perl_quote_buf_with_size(struct strbuf *sb, const char *src, size_t size)
+{
+	const char sq = '\'';
+	const char bq = '\\';
+	char c;
+	size_t cur_size = 0;
+
+	strbuf_addch(sb, sq);
+	while (cur_size < size) {
+		c = *src++;
+		cur_size++;
+
+		if (c == sq || c == bq)
+			strbuf_addch(sb, bq);
+		strbuf_addch(sb, c);
+	}
+	strbuf_addch(sb, sq);
+}
+
 void python_quote_buf(struct strbuf *sb, const char *src)
 {
 	const char sq = '\'';
@@ -492,6 +544,31 @@ void python_quote_buf(struct strbuf *sb, const char *src)
 	strbuf_addch(sb, sq);
 }
 
+void python_quote_buf_with_size(struct strbuf *sb, const char *src, size_t size)
+{
+	const char sq = '\'';
+	const char bq = '\\';
+	const char nl = '\n';
+	char c;
+	size_t cur_size = 0;
+
+	strbuf_addch(sb, sq);
+	while (cur_size < size) {
+		c = *src++;
+		cur_size++;
+
+		if (c == nl) {
+			strbuf_addch(sb, bq);
+			strbuf_addch(sb, 'n');
+			continue;
+		}
+		if (c == sq || c == bq)
+			strbuf_addch(sb, bq);
+		strbuf_addch(sb, c);
+	}
+	strbuf_addch(sb, sq);
+}
+
 void tcl_quote_buf(struct strbuf *sb, const char *src)
 {
 	char c;
@@ -527,6 +604,45 @@ void tcl_quote_buf(struct strbuf *sb, const char *src)
 	strbuf_addch(sb, '"');
 }
 
+void tcl_quote_buf_with_size(struct strbuf *sb, const char *src, size_t size)
+{
+	char c;
+	size_t cur_size = 0;
+
+	strbuf_addch(sb, '"');
+	while (cur_size < size) {
+		c = *src++;
+		cur_size++;
+
+		switch (c) {
+		case '[': case ']':
+		case '{': case '}':
+		case '$': case '\\': case '"':
+			strbuf_addch(sb, '\\');
+			/* fallthrough */
+		default:
+			strbuf_addch(sb, c);
+			break;
+		case '\f':
+			strbuf_addstr(sb, "\\f");
+			break;
+		case '\r':
+			strbuf_addstr(sb, "\\r");
+			break;
+		case '\n':
+			strbuf_addstr(sb, "\\n");
+			break;
+		case '\t':
+			strbuf_addstr(sb, "\\t");
+			break;
+		case '\v':
+			strbuf_addstr(sb, "\\v");
+			break;
+		}
+	}
+	strbuf_addch(sb, '"');
+}
+
 void basic_regex_quote_buf(struct strbuf *sb, const char *src)
 {
 	char c;

quote.h

@@ -30,6 +30,7 @@ struct strbuf;
  */
 
 void sq_quote_buf(struct strbuf *, const char *src);
+void sq_quote_buf_with_size(struct strbuf *, const char *src, size_t size);
 void sq_quote_argv(struct strbuf *, const char **argv);
 void sq_quotef(struct strbuf *, const char *fmt, ...);
 
@@ -94,8 +95,11 @@ char *quote_path(const char *in, const char *prefix, struct strbuf *out, unsigne
 
 /* quoting as a string literal for other languages */
 void perl_quote_buf(struct strbuf *sb, const char *src);
+void perl_quote_buf_with_size(struct strbuf *sb, const char *src, size_t size);
 void python_quote_buf(struct strbuf *sb, const char *src);
+void python_quote_buf_with_size(struct strbuf *sb, const char *src, size_t size);
 void tcl_quote_buf(struct strbuf *sb, const char *src);
+void tcl_quote_buf_with_size(struct strbuf *sb, const char *src, size_t size);
 void basic_regex_quote_buf(struct strbuf *sb, const char *src);
 
 #endif