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[PATCH v17 02/14] ref-filter: introduce ref_formatting_state and ref_formatting_stack

From
Karthik Nayak <karthik.188@gmail.com>
Date
Sep 10, 2015, 15:48 UTC
Message-ID
<1441900110-4015-3-git-send-email-Karthik.188@gmail.com>
In-Reply-To
<1441900110-4015-1-git-send-email-Karthik.188@gmail.com>

Introduce ref_formatting_state which will hold the formatted output strbuf instead of directly printing to stdout. This will help us in creating modifier atoms which modify the format specified before printing to stdout.

Implement a stack machinery for ref_formatting_state, this allows us to push and pop elements onto the stack. Whenever we pop an element from the stack, the strbuf from that element is appended to the strbuf of the next element on the stack, this will allow us to support nesting of modifier atoms.

Rename some functions to reflect the changes made: print_value() -> append_atom() emit() -> append_literal()

Mentored-by: Christian Couder <christian.couder@gmail.com>
Mentored-by: Matthieu Moy <matthieu.moy@grenoble-inp.fr>
Signed-off-by: Karthik Nayak <karthik.188@gmail.com>
---
 ref-filter.c | 78 +++++++++++++++++++++++++++++++++++++++++++++---------------
 1 file changed, 59 insertions(+), 19 deletions(-)
diff --git a/ref-filter.c b/ref-filter.c
index e53c77e..432cea0 100644
--- a/ref-filter.c
+++ b/ref-filter.c
@@ -55,6 +55,18 @@ static struct {
 	{ "color" },
 };
 
+#define REF_FORMATTING_STATE_INIT  { 0, NULL }
+
+struct ref_formatting_stack {
+	struct ref_formatting_stack *prev;
+	struct strbuf output;
+};
+
+struct ref_formatting_state {
+	int quote_style;
+	struct ref_formatting_stack *stack;
+};
+
 struct atom_value {
 	const char *s;
 	unsigned long ul; /* used for sorting when not FIELD_STR */
@@ -129,6 +141,27 @@ int parse_ref_filter_atom(const char *atom, const char *ep)
 	return at;
 }
 
+static void push_stack_element(struct ref_formatting_stack **stack)
+{
+	struct ref_formatting_stack *s = xcalloc(1, sizeof(struct ref_formatting_stack));
+
+	strbuf_init(&s->output, 0);
+	s->prev = *stack;
+	*stack = s;
+}
+
+static void pop_stack_element(struct ref_formatting_stack **stack)
+{
+	struct ref_formatting_stack *current = *stack;
+	struct ref_formatting_stack *prev = current->prev;
+
+	if (prev)
+		strbuf_addbuf(&prev->output, &current->output);
+	strbuf_release(&current->output);
+	free(current);
+	*stack = prev;
+}
+
 /*
  * In a format string, find the next occurrence of %(atom).
  */
@@ -1195,30 +1228,27 @@ void ref_array_sort(struct ref_sorting *sorting, struct ref_array *array)
 	qsort(array->items, array->nr, sizeof(struct ref_array_item *), compare_refs);
 }
 
-static void print_value(struct atom_value *v, int quote_style)
+static void append_atom(struct atom_value *v, struct ref_formatting_state *state)
 {
-	struct strbuf sb = STRBUF_INIT;
-	switch (quote_style) {
+	struct strbuf *s = &state->stack->output;
+
+	switch (state->quote_style) {
 	case QUOTE_NONE:
-		fputs(v->s, stdout);
+		strbuf_addstr(s, v->s);
 		break;
 	case QUOTE_SHELL:
-		sq_quote_buf(&sb, v->s);
+		sq_quote_buf(s, v->s);
 		break;
 	case QUOTE_PERL:
-		perl_quote_buf(&sb, v->s);
+		perl_quote_buf(s, v->s);
 		break;
 	case QUOTE_PYTHON:
-		python_quote_buf(&sb, v->s);
+		python_quote_buf(s, v->s);
 		break;
 	case QUOTE_TCL:
-		tcl_quote_buf(&sb, v->s);
+		tcl_quote_buf(s, v->s);
 		break;
 	}
-	if (quote_style != QUOTE_NONE) {
-		fputs(sb.buf, stdout);
-		strbuf_release(&sb);
-	}
 }
 
 static int hex1(char ch)
@@ -1239,8 +1269,10 @@ static int hex2(const char *cp)
 		return -1;
 }
 
-static void emit(const char *cp, const char *ep)
+static void append_literal(const char *cp, const char *ep, struct ref_formatting_state *state)
 {
+	struct strbuf *s = &state->stack->output;
+
 	while (*cp && (!ep || cp < ep)) {
 		if (*cp == '%') {
 			if (cp[1] == '%')
@@ -1248,13 +1280,13 @@ static void emit(const char *cp, const char *ep)
 			else {
 				int ch = hex2(cp + 1);
 				if (0 <= ch) {
-					putchar(ch);
+					strbuf_addch(s, ch);
 					cp += 3;
 					continue;
 				}
 			}
 		}
-		putchar(*cp);
+		strbuf_addch(s, *cp);
 		cp++;
 	}
 }
@@ -1262,19 +1294,24 @@ static void emit(const char *cp, const char *ep)
 void show_ref_array_item(struct ref_array_item *info, const char *format, int quote_style)
 {
 	const char *cp, *sp, *ep;
+	struct strbuf *final_buf;
+	struct ref_formatting_state state = REF_FORMATTING_STATE_INIT;
+
+	state.quote_style = quote_style;
+	push_stack_element(&state.stack);
 
 	for (cp = format; *cp && (sp = find_next(cp)); cp = ep + 1) {
 		struct atom_value *atomv;
 
 		ep = strchr(sp, ')');
 		if (cp < sp)
-			emit(cp, sp);
+			append_literal(cp, sp, &state);
 		get_ref_atom_value(info, parse_ref_filter_atom(sp + 2, ep), &atomv);
-		print_value(atomv, quote_style);
+		append_atom(atomv, &state);
 	}
 	if (*cp) {
 		sp = cp + strlen(cp);
-		emit(cp, sp);
+		append_literal(cp, sp, &state);
 	}
 	if (need_color_reset_at_eol) {
 		struct atom_value resetv;
@@ -1283,8 +1320,11 @@ void show_ref_array_item(struct ref_array_item *info, const char *format, int qu
 		if (color_parse("reset", color) < 0)
 			die("BUG: couldn't parse 'reset' as a color");
 		resetv.s = color;
-		print_value(&resetv, quote_style);
+		append_atom(&resetv, &state);
 	}
+	final_buf = &state.stack->output;
+	fwrite(final_buf->buf, 1, final_buf->len, stdout);
+	pop_stack_element(&state.stack);
 	putchar('\n');
 }
 

-- 
2.5.1
Previous: Karthik NayakNext: Karthik Nayak
Message 3 of 56 in “port tag.c to use ref-filter APIs”
  1. 00/14 port tag.c to use ref-filter APIsKarthik Nayak, Sep 10, 2015
  2. 01/14 ref-filter: move `struct atom_value` to ref-filter.cKarthik Nayak, Sep 10, 2015
  3. 02/14 ref-filter: introduce ref_formatting_state and ref_formatting_stackKarthik Nayak, Sep 10, 2015
  4. 03/14 utf8: add function to align a string into given strbufKarthik Nayak, Sep 10, 2015
  5. 04/14 ref-filter: introduce handler function for each atomKarthik Nayak, Sep 10, 2015
  6. 05/14 ref-filter: introduce match_atom_name()Karthik Nayak, Sep 10, 2015
  7. Matthieu MoySep 10, 2015
  8. Junio C HamanoSep 10, 2015
  9. Matthieu MoySep 10, 2015
  10. Junio C HamanoSep 10, 2015
  11. Matthieu MoySep 10, 2015
  12. Junio C HamanoSep 10, 2015
  13. Karthik NayakSep 10, 2015
  14. Junio C HamanoSep 10, 2015
  15. Karthik NayakSep 10, 2015
  16. Junio C HamanoSep 10, 2015
  17. Karthik NayakSep 10, 2015
  18. 05/14 ref-filter: introduce match_atom_name()Karthik Nayak, Sep 11, 2015
  19. 06/14 ref-filter: implement an `align` atomKarthik Nayak, Sep 11, 2015
  20. 06/14 ref-filter: implement an `align` atomKarthik Nayak, Sep 10, 2015
  21. Matthieu MoySep 10, 2015
  22. Junio C HamanoSep 10, 2015
  23. 06/14 ref-filter: implement an `align` atomKarthik Nayak, Sep 11, 2015
  24. 07/14 ref-filter: add option to filter out tags, branches and remotesKarthik Nayak, Sep 10, 2015
  25. 08/14 ref-filter: add support for %(contents:lines=X)Karthik Nayak, Sep 10, 2015
  26. Junio C HamanoSep 10, 2015
  27. Karthik NayakSep 10, 2015
  28. 08/14 ref-filter: add support for %(contents:lines=X)Karthik Nayak, Sep 11, 2015
  29. 09/14 ref-filter: add support to sort by versionKarthik Nayak, Sep 10, 2015
  30. 10/14 ref-filter: add option to match literal patternKarthik Nayak, Sep 10, 2015
  31. 11/14 tag.c: use 'ref-filter' data structuresKarthik Nayak, Sep 10, 2015
  32. 12/14 tag.c: use 'ref-filter' APIsKarthik Nayak, Sep 10, 2015
  33. 12/14 tag.c: use 'ref-filter' APIsKarthik Nayak, Sep 11, 2015
  34. 13/14 tag.c: implement '--format' optionKarthik Nayak, Sep 10, 2015
  35. Junio C HamanoSep 10, 2015
  36. Karthik NayakSep 10, 2015
  37. 13/14 tag.c: implement '--format' optionKarthik Nayak, Sep 11, 2015
  38. 14/14 tag.c: implement '--merged' and '--no-merged' optionsKarthik Nayak, Sep 10, 2015
  39. John KeepingSep 17, 2015
  40. Junio C HamanoSep 17, 2015
  41. Matthieu MoySep 18, 2015
  42. John KeepingSep 18, 2015
  43. Matthieu MoySep 18, 2015
  44. Karthik NayakSep 18, 2015
  45. Matthieu MoySep 18, 2015
  46. Karthik NayakSep 18, 2015
  47. Matthieu MoySep 18, 2015
  48. Karthik NayakSep 18, 2015
  49. Matthieu MoySep 18, 2015
  50. Matthieu MoySep 10, 2015
  51. Karthik NayakSep 11, 2015
  52. Eric SunshineSep 11, 2015
  53. Junio C HamanoSep 11, 2015
  54. Karthik NayakSep 11, 2015
  55. Matthieu MoySep 12, 2015
  56. Karthik NayakSep 13, 2015

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