merge(3p/git): Merge git subtree at v2.29.2 r/1890

This also bumps the stable nixpkgs to 20.09 as of 2020-11-21, because
there is some breakage in the git build related to the netrc
credentials helper which someone has taken care of in nixpkgs.

The stable channel is not used for anything other than git, so this
should be fine.

Change-Id: I3575a19dab09e1e9556cf8231d717de9890484fb

1 files changed, 54 insertions, 21 deletions

diff --git a/third_party/git/color.c b/third_party/git/color.c
index ebb222ec33..64f52a4f93 100644
--- a/third_party/git/color.c
+++ b/third_party/git/color.c
@@ -24,6 +24,14 @@ const char *column_colors_ansi[] = {
 	GIT_COLOR_RESET,
 };
 
+enum {
+	COLOR_BACKGROUND_OFFSET = 10,
+	COLOR_FOREGROUND_ANSI = 30,
+	COLOR_FOREGROUND_RGB = 38,
+	COLOR_FOREGROUND_256 = 38,
+	COLOR_FOREGROUND_BRIGHT_ANSI = 90,
+};
+
 /* Ignore the RESET at the end when giving the size */
 const int column_colors_ansi_max = ARRAY_SIZE(column_colors_ansi) - 1;
 
@@ -61,15 +69,38 @@ static int get_hex_color(const char *in, unsigned char *out)
 	return 0;
 }
 
-static int parse_color(struct color *out, const char *name, int len)
+/*
+ * If an ANSI color is recognized in "name", fill "out" and return 0.
+ * Otherwise, leave out unchanged and return -1.
+ */
+static int parse_ansi_color(struct color *out, const char *name, int len)
 {
 	/* Positions in array must match ANSI color codes */
 	static const char * const color_names[] = {
 		"black", "red", "green", "yellow",
 		"blue", "magenta", "cyan", "white"
 	};
-	char *end;
 	int i;
+	int color_offset = COLOR_FOREGROUND_ANSI;
+
+	if (strncasecmp(name, "bright", 6) == 0) {
+		color_offset = COLOR_FOREGROUND_BRIGHT_ANSI;
+		name += 6;
+		len -= 6;
+	}
+	for (i = 0; i < ARRAY_SIZE(color_names); i++) {
+		if (match_word(name, len, color_names[i])) {
+			out->type = COLOR_ANSI;
+			out->value = i + color_offset;
+			return 0;
+		}
+	}
+	return -1;
+}
+
+static int parse_color(struct color *out, const char *name, int len)
+{
+	char *end;
 	long val;
 
 	/* First try the special word "normal"... */
@@ -89,12 +120,8 @@ static int parse_color(struct color *out, const char *name, int len)
 	}
 
 	/* Then pick from our human-readable color names... */
-	for (i = 0; i < ARRAY_SIZE(color_names); i++) {
-		if (match_word(name, len, color_names[i])) {
-			out->type = COLOR_ANSI;
-			out->value = i;
-			return 0;
-		}
+	if (parse_ansi_color(out, name, len) == 0) {
+		return 0;
 	}
 
 	/* And finally try a literal 256-color-mode number */
@@ -109,10 +136,15 @@ static int parse_color(struct color *out, const char *name, int len)
 		else if (val < 0) {
 			out->type = COLOR_NORMAL;
 			return 0;
-		/* Rewrite low numbers as more-portable standard colors. */
+		/* Rewrite 0-7 as more-portable standard colors. */
 		} else if (val < 8) {
 			out->type = COLOR_ANSI;
-			out->value = val;
+			out->value = val + COLOR_FOREGROUND_ANSI;
+			return 0;
+		/* Rewrite 8-15 as more-portable aixterm colors. */
+		} else if (val < 16) {
+			out->type = COLOR_ANSI;
+			out->value = val - 8 + COLOR_FOREGROUND_BRIGHT_ANSI;
 			return 0;
 		} else if (val < 256) {
 			out->type = COLOR_256;
@@ -166,23 +198,26 @@ int color_parse(const char *value, char *dst)
  * already have the ANSI escape code in it. "out" should have enough
  * space in it to fit any color.
  */
-static char *color_output(char *out, int len, const struct color *c, char type)
+static char *color_output(char *out, int len, const struct color *c, int background)
 {
+	int offset = 0;
+
+	if (background)
+		offset = COLOR_BACKGROUND_OFFSET;
 	switch (c->type) {
 	case COLOR_UNSPECIFIED:
 	case COLOR_NORMAL:
 		break;
 	case COLOR_ANSI:
-		if (len < 2)
-			BUG("color parsing ran out of space");
-		*out++ = type;
-		*out++ = '0' + c->value;
+		out += xsnprintf(out, len, "%d", c->value + offset);
 		break;
 	case COLOR_256:
-		out += xsnprintf(out, len, "%c8;5;%d", type, c->value);
+		out += xsnprintf(out, len, "%d;5;%d", COLOR_FOREGROUND_256 + offset,
+				 c->value);
 		break;
 	case COLOR_RGB:
-		out += xsnprintf(out, len, "%c8;2;%d;%d;%d", type,
+		out += xsnprintf(out, len, "%d;2;%d;%d;%d",
+				 COLOR_FOREGROUND_RGB + offset,
 				 c->red, c->green, c->blue);
 		break;
 	}
@@ -279,14 +314,12 @@ int color_parse_mem(const char *value, int value_len, char *dst)
 		if (!color_empty(&fg)) {
 			if (sep++)
 				OUT(';');
-			/* foreground colors are all in the 3x range */
-			dst = color_output(dst, end - dst, &fg, '3');
+			dst = color_output(dst, end - dst, &fg, 0);
 		}
 		if (!color_empty(&bg)) {
 			if (sep++)
 				OUT(';');
-			/* background colors are all in the 4x range */
-			dst = color_output(dst, end - dst, &bg, '4');
+			dst = color_output(dst, end - dst, &bg, 1);
 		}
 		OUT('m');
 	}