sgr(): New function (4-bit colors only)

4 files changed, 123 insertions, 0 deletions

diff --git a/src/local.mk b/src/local.mk
index 43f5c4a..24d8af2 100644
--- a/src/local.mk
+++ b/src/local.mk
@@ -2,4 +2,5 @@ fbcon2png_SOURCES += \
 	%reldir%/font.c \
 	%reldir%/image.c \
 	%reldir%/main.c \
+	%reldir%/sgr.c \
 	%reldir%/text.c
diff --git a/src/sgr.c b/src/sgr.c
new file mode 100644
index 0000000..baec803
--- /dev/null
+++ b/src/sgr.c
@@ -0,0 +1,85 @@
+/*
+ * Select Graphic Rendition color parameters function
+ *
+ * Copyright (C) 2019  Patrick McDermott
+ *
+ * This file is part of fbcon2png.
+ *
+ * fbcon2png is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * fbcon2png is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with fbcon2png.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "sgr.h"
+
+#include <stdlib.h>
+#include <string.h>
+
+#include <png.h>
+
+static png_color _4bit[] = {
+	{  0,   0,   0},  /* Black */
+	{170,   0,   0},  /* Red */
+	{  0, 170,   0},  /* Green */
+	{170,  85,   0},  /* Yellow */
+	{  0,   0, 170},  /* Blue */
+	{170,   0, 170},  /* Magenta */
+	{  0, 170, 170},  /* Cyan */
+	{170, 170, 170},  /* White */
+	{ 85,  85,  85},  /* Bright Black */
+	{255,  85,  85},  /* Bright Red */
+	{ 85, 255,  85},  /* Bright Green */
+	{255, 255,  85},  /* Bright Yellow */
+	{ 85,  85, 255},  /* Bright Blue */
+	{255,  85, 255},  /* Bright Magenta */
+	{ 85, 255, 255},  /* Bright Cyan */
+	{255, 255, 255},  /* Bright White */
+};
+
+/* TODO: Add 8-bit and 24-bit modes. */
+
+void
+sgr(char *param, png_colorp fg, png_colorp bg)
+{
+	int   end;
+	char *p;
+	int   i;
+
+	end = 0;
+	for (p = param; param; ++param) {
+		if (*param == ';' || *param == ':' || *param == '\0') {
+			if (*param == '\0') {
+				end = 1;
+			}
+			*param = '\0';
+			i = atoi(p);
+			if (i >= 30 && i <= 37) {  /* Set foreground color */
+				memcpy(fg, &_4bit[i - 30], sizeof(*fg));
+			}
+			if (i >= 40 && i <= 47) {  /* Set background color */
+				memcpy(bg, &_4bit[i - 40], sizeof(*bg));
+			}
+			if (i >= 90 && i <= 97) {  /* Set foreground color */
+				memcpy(fg, &_4bit[i - 90 + 8], sizeof(*fg));
+			}
+			if (i >= 100 && i <= 107) {  /* Set background color */
+				memcpy(bg, &_4bit[i - 100 + 8], sizeof(*bg));
+			}
+			if (end) {
+				break;
+			}
+			p = param + 1;
+		} else if (*param < '0' || *param > '9') {
+			break;
+		}
+	}
+}
diff --git a/src/sgr.h b/src/sgr.h
new file mode 100644
index 0000000..3b2362e
--- /dev/null
+++ b/src/sgr.h
@@ -0,0 +1,30 @@
+/*
+ * Select Graphic Rendition color parameters function
+ *
+ * Copyright (C) 2019  Patrick McDermott
+ *
+ * This file is part of fbcon2png.
+ *
+ * fbcon2png is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * fbcon2png is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with fbcon2png.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef SRG_H_
+#define SGR_H_
+
+#include <png.h>
+
+void
+sgr(char *param, png_colorp fg, png_colorp bg);
+
+#endif  /* SGR_H_ */
diff --git a/src/text.c b/src/text.c
index cb777e4..1d888d8 100644
--- a/src/text.c
+++ b/src/text.c
@@ -27,6 +27,7 @@
 #include <png.h>
 
 #include "font.h"
+#include "sgr.h"
 
 #define MAX(a, b) (((a) > (b)) ? (a) : (b))
 
@@ -102,6 +103,7 @@ text_render(struct text *text, struct font *font, png_bytepp rows)
 	char      *string;
 	size_t     row;
 	size_t     col;
+	char      *parameter;
 	png_color  fg = {255, 255, 255};
 	png_color  bg = {  0,   0,   0};
 
@@ -117,9 +119,14 @@ text_render(struct text *text, struct font *font, png_bytepp rows)
 	while (string && *string) {
 		if (*string == 0x1B && *(string + 1) == '[') {  /* CSI */
 			string += 2;
+			parameter = string;
 			for (; *string >= 0x30 && *string <= 0x3F; ++string);
 			for (; *string >= 0x20 && *string <= 0x2F; ++string);
 			if (*string >= 0x40 && *string <= 0x7E) {
+				if (*string == 'm') {
+					*string = '\0';
+					sgr(parameter, &fg, &bg);
+				}
 				++string;
 			}
 		} else if (*string == '\n') {