Add a shared-memory framebuffer output method

Signed-off-by: Jeremy Kerr <jk@ozlabs.org>

5 files changed, 215 insertions, 4 deletions

diff --git a/src/Makefile.am b/src/Makefile.am
index e99f752..d942176 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -4,7 +4,7 @@ bin_PROGRAMS = fbterm
 
 fbterm_SOURCES = fbconfig.cpp fbconfig.h fbio.cpp fbio.h fbshell.cpp fbshell.h fbshellman.cpp fbshellman.h fbterm.cpp \
 	fbterm.h font.cpp font.h input.cpp input.h input_key.h mouse.cpp mouse.h screen.cpp screen.h improxy.cpp improxy.h \
-	screen_render.cpp fbdev.cpp fbdev.h vesadev.cpp vesadev.h vbe.h
+	screen_render.cpp fbdev.cpp fbdev.h fbshm.cpp fbshm.h vesadev.cpp vesadev.h vbe.h
 EXTRA_fbterm_SOURCES = signalfd.h
 
 fbterm_CXXFLAGS = -fno-exceptions -fno-rtti -I$(top_srcdir)/src/lib @FT2_CFLAGS@ @FC_CFLAGS@
diff --git a/src/fbconfig.cpp b/src/fbconfig.cpp
index 14240b6..f1985d0 100644
--- a/src/fbconfig.cpp
+++ b/src/fbconfig.cpp
@@ -237,6 +237,7 @@ bool Config::parseArgs(s32 argc, s8 **argv)
 		{ "font-width", required_argument, 0, 2 },
 		{ "font-height", required_argument, 0, 4 },
 		{ "ambiguous-wide", no_argument, 0, 'a' },
+		{ "shared-mem", required_argument, 0, 'm' },
 #ifdef ENABLE_VESA
 		{ "vesa-mode", required_argument, 0, 3 },
 #endif
@@ -244,7 +245,7 @@ bool Config::parseArgs(s32 argc, s8 **argv)
 	};
 
 	s32 index;
-	while ((index = getopt_long(argc, argv, "Vvhn:s:f:b:e:r:i:a", options, 0)) != -1) {
+	while ((index = getopt_long(argc, argv, "Vvhn:s:f:b:e:r:i:m:a", options, 0)) != -1) {
 		switch (index) {
 		case 'V':
 			printf("FbTerm version " VERSION "\n");
@@ -269,6 +270,7 @@ bool Config::parseArgs(s32 argc, s8 **argv)
 				"  -r, --screen-rotate=NUM         specify orientation of screen display\n"
 				"  -a, --ambiguous-wide            treat ambiguous width characters as wide\n"
 				"  -i, --input-method=TEXT         specify input method program\n"
+				"  -m, --shared-mem=DESC           use shared-memory framebuffer DESC\n"
 				"      --cursor-shape=NUM          specify default cursor shape\n"
 				"      --cursor-interval=NUM       specify cursor flash interval\n"
 #ifdef ENABLE_VESA
diff --git a/src/fbshm.cpp b/src/fbshm.cpp
new file mode 100644
index 0000000..48d0c38
--- /dev/null
+++ b/src/fbshm.cpp
@@ -0,0 +1,157 @@
+/*
+ *   Copyright © 2018 IBM Corporation
+ *   This file is part of FbTerm.
+ *
+ *   This program 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.
+ *
+ *   This program 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 this program; if not, write to the Free Software
+ *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ *
+ */
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <sys/mman.h>
+#include "fbconfig.h"
+#include "fbshm.h"
+
+int FbShm::parse_shm_desc(const char *desc, char **file,
+		int *rows, int *cols, int *bpp)
+{
+	char *str, *sep, *endp;
+	unsigned long tmp;
+
+	str = strdup(desc);
+
+	/* <file>:<cols>x<rows>@<bpp> */
+
+	/* file */
+	sep = strchr(str, ':');
+	if (!sep)
+		goto err_free;
+
+	*file = str;
+	*sep = '\0';
+
+	/* cols */
+	str = sep + 1;
+	sep = strchr(str, 'x');
+	if (!sep) {
+		fprintf(stderr, "can't parse shm descriptor %s: no geom\n",
+				desc);
+		goto err_free;
+	}
+	*sep = '\0';
+
+	tmp = strtoul(str, &endp, 10);
+	if (endp != sep) {
+		fprintf(stderr,
+			"can't parse shm descriptor %s: invalid cols %s\n",
+			desc, str);
+		goto err_free;
+	}
+
+	*cols = (int)(tmp & 0xffffffff);
+
+	/* rows */
+	str = sep + 1;
+	sep = strchr(str, '@');
+	if (!sep) {
+		fprintf(stderr, "can't parse shm descriptor %s: no geom\n",
+				desc);
+		goto err_free;
+	}
+	*sep = '\0';
+
+	tmp = strtoul(str, &endp, 10);
+	if (endp != sep) {
+		fprintf(stderr,
+			"can't parse shm descriptor %s: invalid rows %s\n",
+			desc, str);
+		goto err_free;
+	}
+
+	*rows = (int)(tmp & 0xffffffff);
+
+	/* bpp */
+	tmp = strtoul(sep + 1, &endp, 10);
+	if (*endp != '\0' || endp == str) {
+		fprintf(stderr,
+			"can't parse shm descriptor %s: invalid bpp\n",
+			desc);
+		goto err_free;
+	}
+
+	*bpp = (int)(tmp & 0xff);
+
+	printf("%s: rows %d, cols %d, bpp %d\n", *file, *rows, *cols, *bpp);
+
+	return 0;
+
+err_free:
+	free(str);
+	return -1;
+}
+
+FbShm *FbShm::initFbShm()
+{
+	int rows, cols, bpp;
+	s8 *file, desc[4096];
+	int fd;
+
+	Config::instance()->getOption("shared-mem", desc, sizeof(desc));
+
+	if (!strlen(desc))
+		return 0;
+
+	if (parse_shm_desc(desc, &file, &rows, &cols, &bpp))
+		return 0;
+
+	fd = open(file, O_RDWR);
+	if (fd < 0) {
+		fprintf(stderr, "can't open frame buffer shm %s: %m\n", file);
+		free(file);
+		return 0;
+	}
+
+	free(file);
+
+	return new FbShm(fd, rows, cols, bpp);
+}
+
+FbShm::FbShm(int fd, int rows, int cols, int bpp)
+{
+	mWidth = cols;
+	mHeight = rows;
+	mBitsPerPixel = bpp;
+	mBytesPerLine = cols * (bpp >> 3);
+	mFD = fd;
+
+
+	mVMemBase = (u8 *)mmap(0, mHeight * mBytesPerLine,
+			PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0);
+}
+
+FbShm::~FbShm()
+{
+	munmap(mVMemBase, mHeight * mBytesPerLine);
+	close(mFD);
+}
+
+const s8 *FbShm::drvId()
+{
+	return "shm";
+}
+
diff --git a/src/fbshm.h b/src/fbshm.h
new file mode 100644
index 0000000..3b85726
--- /dev/null
+++ b/src/fbshm.h
@@ -0,0 +1,39 @@
+/*
+ *   Copyright © 2018 IBM Corporation
+ *   This file is part of FbTerm.
+ *
+ *   This program 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.
+ *
+ *   This program 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 this program; if not, write to the Free Software
+ *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ *
+ */
+
+#ifndef FBSHM_H
+#define FBSHM_H
+
+#include "screen.h"
+
+class FbShm : public Screen {
+private:
+	friend class Screen;
+	static FbShm *initFbShm();
+	static int parse_shm_desc(const char *desc, char **file,
+			int *rows, int *cols, int *bpp);
+	int mFD;
+
+	FbShm(int fd, int rows, int cols, int bpp);
+	~FbShm();
+
+	virtual const s8 *drvId();
+};
+#endif
diff --git a/src/screen.cpp b/src/screen.cpp
index 4da2453..fee1f05 100644
--- a/src/screen.cpp
+++ b/src/screen.cpp
@@ -26,6 +26,7 @@
 #include "fbshellman.h"
 #include "fbconfig.h"
 #include "fbdev.h"
+#include "fbshm.h"
 #include "config.h"
 #ifdef ENABLE_VESA
 #include "vesadev.h"
@@ -45,6 +46,7 @@ DEFINE_INSTANCE(Screen)
 
 Screen *Screen::createInstance()
 {
+
 	if (!Font::instance() || !FW(1) || !FH(1)) {
 		fprintf(stderr, "init font error!\n");
 		return 0;
@@ -52,6 +54,9 @@ Screen *Screen::createInstance()
 
 	Screen *pScreen = 0;
 
+	s8 shm_info[2];
+	Config::instance()->getOption("shared-mem", shm_info, sizeof(shm_info));
+
 #ifdef ENABLE_VESA
 	s8 buf[16];
 	Config::instance()->getOption("vesa-mode", buf, sizeof(buf));
@@ -63,10 +68,18 @@ Screen *Screen::createInstance()
 	u32 mode = 0;
 	Config::instance()->getOption("vesa-mode", mode);
 
-	if (!mode) pScreen = FbDev::initFbDev();
+	if (!mode) {
+		if (strlen(shm_info))
+			pScreen = FbShm::initFbShm();
+		else
+			pScreen = FbDev::initFbDev();
+	}
 	if (!pScreen) pScreen = VesaDev::initVesaDev(mode);
 #else
-	pScreen = FbDev::initFbDev();
+	if (strlen(shm_info))
+		pScreen = FbShm::initFbShm();
+	else
+		pScreen = FbDev::initFbDev();
 #endif
 
 	if (!pScreen) return 0;