git/list[1] front-page[2] threads[3] people[4] search[5] about
 

[PATCHv5 04/17] diff: introduce more flexible emit function

From
Stefan Beller <sbeller@google.com>
Date
May 24, 2017, 21:40 UTC
Message-ID
<20170524214036.29623-5-sbeller@google.com>
In-Reply-To
<20170524214036.29623-1-sbeller@google.com>

Currently, diff output is written either through the emit_line_0 function or through the FILE * in struct diff_options directly. To make it easier to teach diff to buffer its output (which will be done in a subsequent commit), introduce a more flexible emit_line() function. In this commit, direct usages of emit_line_0() are replaced with emit_line(); subsequent commits will also replace usages of the FILE * with emit().

Instead of having a 'first' parameter containing the first character of a line, have a dedicated 'sign' parameter that is just set when the first character of the line is part of the actual content, i.e. ' ', '+', '-'.

Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
---
 diff.c | 76 +++++++++++++++++++++++++++++-------------------------------------
 1 file changed, 33 insertions(+), 43 deletions(-)
diff --git a/diff.c b/diff.c
index 2f9722b382..3569857818 100644
--- a/diff.c
+++ b/diff.c
@@ -516,36 +516,30 @@ static void check_blank_at_eof(mmfile_t *mf1, mmfile_t *mf2,
 	ecbdata->blank_at_eof_in_postimage = (at - l2) + 1;
 }
 
-static void emit_line_0(struct diff_options *o, const char *set, const char *reset,
-			int first, const char *line, int len)
+static void emit_line(struct diff_options *o, const char *set, const char *reset,
+		      int add_line_prefix, int sign, const char *line, int len)
 {
 	int has_trailing_newline, has_trailing_carriage_return;
-	int nofirst;
 	FILE *file = o->file;
 
-	fputs(diff_line_prefix(o), file);
+	if (add_line_prefix)
+		fputs(diff_line_prefix(o), file);
 
-	if (len == 0) {
-		has_trailing_newline = (first == '\n');
-		has_trailing_carriage_return = (!has_trailing_newline &&
-						(first == '\r'));
-		nofirst = has_trailing_newline || has_trailing_carriage_return;
-	} else {
-		has_trailing_newline = (len > 0 && line[len-1] == '\n');
-		if (has_trailing_newline)
-			len--;
-		has_trailing_carriage_return = (len > 0 && line[len-1] == '\r');
-		if (has_trailing_carriage_return)
-			len--;
-		nofirst = 0;
-	}
+	has_trailing_newline = (len > 0 && line[len-1] == '\n');
+	if (has_trailing_newline)
+		len--;
+	has_trailing_carriage_return = (len > 0 && line[len-1] == '\r');
+	if (has_trailing_carriage_return)
+		len--;
 
-	if (len || !nofirst) {
-		fputs(set, file);
-		if (!nofirst)
-			fputc(first, file);
+	if (len || sign) {
+		if (set)
+			fputs(set, file);
+		if (sign)
+			fputc(sign, file);
 		fwrite(line, len, 1, file);
-		fputs(reset, file);
+		if (reset)
+			fputs(reset, file);
 	}
 	if (has_trailing_carriage_return)
 		fputc('\r', file);
@@ -553,12 +547,6 @@ static void emit_line_0(struct diff_options *o, const char *set, const char *res
 		fputc('\n', file);
 }
 
-static void emit_line(struct diff_options *o, const char *set, const char *reset,
-		      const char *line, int len)
-{
-	emit_line_0(o, set, reset, line[0], line+1, len-1);
-}
-
 static int new_blank_line_at_eof(struct emit_callback *ecbdata, const char *line, int len)
 {
 	if (!((ecbdata->ws_rule & WS_BLANK_AT_EOF) &&
@@ -587,13 +575,13 @@ static void emit_line_checked(const char *reset,
 	}
 
 	if (!ws)
-		emit_line_0(ecbdata->opt, set, reset, sign, line, len);
+		emit_line(ecbdata->opt, set, reset, 1, sign, line, len);
 	else if (sign == '+' && new_blank_line_at_eof(ecbdata, line, len))
 		/* Blank line at EOF - paint '+' as well */
-		emit_line_0(ecbdata->opt, ws, reset, sign, line, len);
+		emit_line(ecbdata->opt, ws, reset, 1, sign, line, len);
 	else {
 		/* Emit just the prefix, then the rest. */
-		emit_line_0(ecbdata->opt, set, reset, sign, "", 0);
+		emit_line(ecbdata->opt, set, reset, 1, sign, "", 0);
 		ws_check_emit(line, len, ecbdata->ws_rule,
 			      ecbdata->opt->file, set, reset, ws);
 	}
@@ -643,7 +631,7 @@ static void emit_hunk_header(struct emit_callback *ecbdata,
 	if (len < 10 ||
 	    memcmp(line, atat, 2) ||
 	    !(ep = memmem(line + 2, len - 2, atat, 2))) {
-		emit_line(ecbdata->opt, context, reset, line, len);
+		emit_line(ecbdata->opt, context, reset, 1, 0, line, len);
 		return;
 	}
 	ep += 2; /* skip over @@ */
@@ -679,7 +667,7 @@ static void emit_hunk_header(struct emit_callback *ecbdata,
 	strbuf_add(&msgbuf, line + len, org_len - len);
 	strbuf_complete_line(&msgbuf);
 
-	emit_line(ecbdata->opt, "", "", msgbuf.buf, msgbuf.len);
+	emit_line(ecbdata->opt, "", "", 1, 0, msgbuf.buf, msgbuf.len);
 	strbuf_release(&msgbuf);
 }
 
@@ -742,8 +730,8 @@ static void emit_rewrite_lines(struct emit_callback *ecb,
 		const char *context = diff_get_color(ecb->color_diff,
 						     DIFF_CONTEXT);
 		putc('\n', ecb->opt->file);
-		emit_line_0(ecb->opt, context, reset, '\\',
-			    nneof, strlen(nneof));
+		emit_line(ecb->opt, context, reset, 1, '\\',
+			  nneof, strlen(nneof));
 	}
 }
 
@@ -1341,7 +1329,7 @@ static void fn_out_consume(void *priv, char *line, unsigned long len)
 		}
 		diff_words_flush(ecbdata);
 		if (ecbdata->diff_words->type == DIFF_WORDS_PORCELAIN) {
-			emit_line(o, context, reset, line, len);
+			emit_line(o, context, reset, 1, 0, line, len);
 			fputs("~\n", o->file);
 		} else {
 			/*
@@ -1353,7 +1341,7 @@ static void fn_out_consume(void *priv, char *line, unsigned long len)
 			      line++;
 			      len--;
 			}
-			emit_line(o, context, reset, line, len);
+			emit_line(o, context, reset, 1, 0, line, len);
 		}
 		return;
 	}
@@ -1376,7 +1364,7 @@ static void fn_out_consume(void *priv, char *line, unsigned long len)
 		/* incomplete line at the end */
 		ecbdata->lno_in_preimage++;
 		emit_line(o, diff_get_color(ecbdata->color_diff, DIFF_CONTEXT),
-			  reset, line, len);
+			  reset, 1, 0, line, len);
 		break;
 	}
 }
@@ -2188,7 +2176,7 @@ static void checkdiff_consume(void *priv, char *line, unsigned long len)
 		fprintf(data->o->file, "%s%s:%d: %s.\n",
 			line_prefix, data->filename, data->lineno, err);
 		free(err);
-		emit_line(data->o, set, reset, line, 1);
+		emit_line(data->o, set, reset, 1, 0, line, 1);
 		ws_check_emit(line + 1, len - 1, data->ws_rule,
 			      data->o->file, set, reset, ws);
 	} else if (line[0] == ' ') {
@@ -4833,9 +4821,11 @@ void diff_flush(struct diff_options *options)
 
 	if (output_format & DIFF_FORMAT_PATCH) {
 		if (separator) {
-			fprintf(options->file, "%s%c",
-				diff_line_prefix(options),
-				options->line_termination);
+			char term[2];
+			term[0] = options->line_termination;
+			term[1] = '\0';
+
+			emit_line(options, NULL, NULL, 1, 0, term, !!term[0]);
 			if (options->stat_sep) {
 				/* attach patch instead of inline */
 				fputs(options->stat_sep, options->file);

-- 
2.13.0.18.g7d86cc8ba0
Previous: Stefan BellerNext: Jonathan Tan
Message 5 of 125 in “[PATCHv5 00/17] Diff machine: highlight moved lines.”
  1. Stefan BellerMay 24, 2017
  2. 01/17 diff: readability fixStefan Beller, May 24, 2017
  3. 03/17 diff.c: factor out diff_flush_patch_all_file_pairsStefan Beller, May 24, 2017
  4. 09/17 submodule.c: convert show_submodule_summary to use emit_line_fmtStefan Beller, May 24, 2017
  5. 04/17 diff: introduce more flexible emit functionStefan Beller, May 24, 2017
  6. Jonathan TanJun 13, 2017
  7. Stefan BellerJun 13, 2017
  8. Jonathan TanJun 13, 2017
  9. 05/17 diff.c: convert fn_out_consume to use emit_lineStefan Beller, May 24, 2017
  10. 02/17 diff: move line ending check into emit_hunk_headerStefan Beller, May 24, 2017
  11. 07/17 diff.c: convert emit_rewrite_diff to use emit_line_*Stefan Beller, May 24, 2017
  12. 15/17 diff.c: emit_line includes whitespace highlightingStefan Beller, May 24, 2017
  13. 11/17 diff.c: convert show_stats to use emit_line_*Stefan Beller, May 24, 2017
  14. 17/17 diff.c: color moved lines differentlyStefan Beller, May 24, 2017
  15. Junio C HamanoMay 25, 2017
  16. Stefan BellerMay 25, 2017
  17. 10/17 diff.c: convert emit_binary_diff_body to use emit_line_*Stefan Beller, May 24, 2017
  18. 08/17 diff.c: convert emit_rewrite_lines to use emit_line_*Stefan Beller, May 24, 2017
  19. 16/17 diff: buffer all output if asked toStefan Beller, May 24, 2017
  20. Junio C HamanoMay 25, 2017
  21. Stefan BellerMay 25, 2017
  22. Junio C HamanoMay 26, 2017
  23. Jonathan TanJun 13, 2017
  24. Stefan BellerJun 14, 2017
  25. 12/17 diff.c: convert word diffing to use emit_line_*Stefan Beller, May 24, 2017
  26. 14/17 diff.c: convert diff_summary to use emit_line_*Stefan Beller, May 24, 2017
  27. 13/17 diff.c: convert diff_flush to use emit_line_*Stefan Beller, May 24, 2017
  28. 06/17 diff.c: convert builtin_diff to use emit_line_*Stefan Beller, May 24, 2017
  29. Junio C HamanoMay 25, 2017
  30. Stefan BellerMay 25, 2017
  31. Junio C HamanoMay 26, 2017
  32. Stefan BellerMay 26, 2017
  33. 0/1 Diff machine: highlight moved lines.Stefan Beller, May 27, 2017
  34. 1/1 diff.c: color moved lines differentlyStefan Beller, May 27, 2017
  35. Philip OakleyMay 27, 2017
  36. Stefan BellerMay 30, 2017
  37. diff.c: color moved lines differentlyStefan Beller, Jun 1, 2017
  38. Jonathan TanJun 13, 2017
  39. Stefan BellerJun 14, 2017
  40. 00/26 reroll of sb/diff-color-movedStefan Beller, Jun 20, 2017
  41. 02/26 diff.c: move line ending check into emit_hunk_headerStefan Beller, Jun 20, 2017
  42. 03/26 diff.c: factor out diff_flush_patch_all_file_pairsStefan Beller, Jun 20, 2017
  43. 06/26 diff.c: emit_diff_symbol learns DIFF_SYMBOL_CONTEXT_FRAGINFOStefan Beller, Jun 20, 2017
  44. 07/26 diff.c: emit_diff_symbol learns DIFF_SYMBOL_NO_LF_EOFStefan Beller, Jun 20, 2017
  45. 08/26 diff.c: migrate emit_line_checked to use emit_diff_symbolStefan Beller, Jun 20, 2017
  46. Junio C HamanoJun 21, 2017
  47. Stefan BellerJun 22, 2017
  48. Stefan BellerJun 22, 2017
  49. Junio C HamanoJun 23, 2017
  50. 11/26 diff.c: emit_diff_symbol learns DIFF_SYMBOL_FILEPAIRStefan Beller, Jun 20, 2017
  51. Jonathan TanJun 20, 2017
  52. Junio C HamanoJun 21, 2017
  53. Stefan BellerJun 22, 2017
  54. 04/26 diff.c: introduce emit_diff_symbolStefan Beller, Jun 20, 2017
  55. Junio C HamanoJun 21, 2017
  56. Stefan BellerJun 21, 2017
  57. Junio C HamanoJun 21, 2017
  58. Junio C HamanoJun 21, 2017
  59. Stefan BellerJun 21, 2017
  60. Junio C HamanoJun 21, 2017
  61. Stefan BellerJun 21, 2017
  62. Brandon WilliamsJun 21, 2017
  63. Junio C HamanoJun 21, 2017
  64. Brandon WilliamsJun 21, 2017
  65. 15/26 submodule.c: migrate diff output to use emit_diff_symbolStefan Beller, Jun 20, 2017
  66. Jonathan TanJun 20, 2017
  67. 19/26 diff.c: emit_diff_symbol learns about DIFF_SYMBOL_STAT_SEPStefan Beller, Jun 20, 2017
  68. 12/26 diff.c: emit_diff_symbol learns DIFF_SYMBOL_HEADERStefan Beller, Jun 20, 2017
  69. 17/26 diff.c: convert show_stats to use emit_diff_symbolStefan Beller, Jun 20, 2017
  70. Brandon WilliamsJun 21, 2017
  71. Stefan BellerJun 21, 2017
  72. 18/26 diff.c: convert word diffing to use emit_diff_symbolStefan Beller, Jun 20, 2017
  73. 25/26 diff: document the new --color-moved settingStefan Beller, Jun 20, 2017
  74. 14/26 diff.c: emit_diff_symbol learns DIFF_SYMBOL_REWRITE_DIFFStefan Beller, Jun 20, 2017
  75. 26/26 diff.c: have a "machine parseable" move coloringStefan Beller, Jun 20, 2017
  76. Stefan BellerJun 20, 2017
  77. Ævar Arnfjörð BjarmasonJun 23, 2017
  78. Brandon WilliamsJun 21, 2017
  79. Junio C HamanoJun 21, 2017
  80. Stefan BellerJun 21, 2017
  81. 20/26 diff.c: emit_diff_symbol learns about DIFF_SYMBOL_SUMMARYStefan Beller, Jun 20, 2017
  82. 21/26 diff.c: buffer all output if asked toStefan Beller, Jun 20, 2017
  83. 24/26 diff.c: add dimming to moved line detectionStefan Beller, Jun 20, 2017
  84. Junio C HamanoJun 21, 2017
  85. 16/26 diff.c: convert emit_binary_diff_body to use emit_diff_symbolStefan Beller, Jun 20, 2017
  86. Junio C HamanoJun 21, 2017
  87. 23/26 diff.c: color moved lines differently, plain modeStefan Beller, Jun 20, 2017
  88. 09/26 diff.c: emit_diff_symbol learns DIFF_SYMBOL_WORDS{_PORCELAIN}Stefan Beller, Jun 20, 2017
  89. 22/26 diff.c: color moved lines differentlyStefan Beller, Jun 20, 2017
  90. Jonathan TanJun 20, 2017
  91. Stefan BellerJun 20, 2017
  92. 05/26 diff.c: emit_diff_symbol learns DIFF_SYMBOL_CONTEXT_MARKERStefan Beller, Jun 20, 2017
  93. 10/26 diff.c: emit_diff_symbol learns DIFF_SYMBOL_CONTEXT_INCOMPLETEStefan Beller, Jun 20, 2017
  94. 13/26 diff.c: emit_diff_symbol learns about DIFF_SYMBOL_BINARY_FILESStefan Beller, Jun 20, 2017
  95. Junio C HamanoJun 21, 2017
  96. Stefan BellerJun 21, 2017
  97. 01/26 diff.c: readability fixStefan Beller, Jun 20, 2017
  98. 00/25 reroll of sb/diff-color-movedStefan Beller, Jun 23, 2017
  99. 02/25 diff.c: move line ending check into emit_hunk_headerStefan Beller, Jun 23, 2017
  100. 04/25 diff.c: introduce emit_diff_symbolStefan Beller, Jun 23, 2017
  101. Junio C HamanoJun 23, 2017
  102. Stefan BellerJun 23, 2017
  103. 06/25 diff.c: emit_diff_symbol learns DIFF_SYMBOL_CONTEXT_FRAGINFOStefan Beller, Jun 23, 2017
  104. 03/25 diff.c: factor out diff_flush_patch_all_file_pairsStefan Beller, Jun 23, 2017
  105. 05/25 diff.c: emit_diff_symbol learns DIFF_SYMBOL_CONTEXT_MARKERStefan Beller, Jun 23, 2017
  106. 09/25 diff.c: emit_diff_symbol learns DIFF_SYMBOL_WORDS[_PORCELAIN]Stefan Beller, Jun 23, 2017
  107. 07/25 diff.c: emit_diff_symbol learns DIFF_SYMBOL_NO_LF_EOFStefan Beller, Jun 23, 2017
  108. 13/25 diff.c: emit_diff_symbol learns about DIFF_SYMBOL_BINARY_FILESStefan Beller, Jun 23, 2017
  109. 12/25 diff.c: emit_diff_symbol learns DIFF_SYMBOL_HEADERStefan Beller, Jun 23, 2017
  110. 14/25 diff.c: emit_diff_symbol learns DIFF_SYMBOL_REWRITE_DIFFStefan Beller, Jun 23, 2017
  111. 23/25 diff.c: color moved lines differently, plain modeStefan Beller, Jun 23, 2017
  112. 22/25 diff.c: color moved lines differentlyStefan Beller, Jun 23, 2017
  113. 15/25 submodule.c: migrate diff output to use emit_diff_symbolStefan Beller, Jun 23, 2017
  114. 25/25 diff: document the new --color-moved settingStefan Beller, Jun 23, 2017
  115. 11/25 diff.c: emit_diff_symbol learns DIFF_SYMBOL_FILEPAIR_{PLUS, MINUS}Stefan Beller, Jun 23, 2017
  116. 24/25 diff.c: add dimming to moved line detectionStefan Beller, Jun 23, 2017
  117. 01/25 diff.c: readability fixStefan Beller, Jun 23, 2017
  118. 10/25 diff.c: emit_diff_symbol learns DIFF_SYMBOL_CONTEXT_INCOMPLETEStefan Beller, Jun 23, 2017
  119. 21/25 diff.c: buffer all output if asked toStefan Beller, Jun 23, 2017
  120. 08/25 diff.c: migrate emit_line_checked to use emit_diff_symbolStefan Beller, Jun 23, 2017
  121. 18/25 diff.c: convert word diffing to use emit_diff_symbolStefan Beller, Jun 23, 2017
  122. 17/25 diff.c: convert show_stats to use emit_diff_symbolStefan Beller, Jun 23, 2017
  123. 19/25 diff.c: emit_diff_symbol learns about DIFF_SYMBOL_STAT_SEPStefan Beller, Jun 23, 2017
  124. 20/25 diff.c: emit_diff_symbol learns about DIFF_SYMBOL_SUMMARYStefan Beller, Jun 23, 2017
  125. 16/25 diff.c: convert emit_binary_diff_body to use emit_diff_symbolStefan Beller, Jun 23, 2017

Read the whole thread, see it on lore, or plain text.

$ cat FOOTERMessages come from the public archive at lore.kernel.org/git, fetched every hour. The front page is chosen and written each morning by an AI editor and can be wrong; the threads themselves are the record. About and API. For agents: an MCP server at https://gitlist.dev/mcp, and any thread, story or person page as Markdown by adding .md to its URL (or sending Accept: text/markdown). Details in /llms.txt.