Hi,
Changes in [PATCH v5]:
Fix-incorrect-signal-handling.patch:
Fix compiler warnings about implicit declaration of bogl_signal().
Font-scaler.patch
Use a lookup table to speed up font scaling.
=======
I'm sorry for sending a lot of emails to you, but I think this email is
probably the last one of this email series. :-)
Best Regards,
Zhang Boyang
From 7d399b7223bc194c0b61aab8c6bd252fd0d43ded Mon Sep 17 00:00:00 2001
From: Zhang Boyang <zhangboyang...@gmail.com>
Date: Tue, 24 May 2022 12:58:01 +0800
Subject: [PATCH v5 2/4] Fix incorrect signal handling
There are problems in signal handlers. Signal handlers must not call any
non-async-signal-safe functions, and they must save-restore errno if
errno is modified inside signal handlers. This patch fixes these
problems by deferring real tasks to main loop. This patch also
introduces bogl_signal(), which wraps around sigaction() thus signal
handlers can be installed in a portable way. Since signal related
problems are fixed, the previously temporarily disabled font unmapping
is now re-enabled.
---
bogl.c | 50 +++++++++++++++++++++++++-------------------------
bogl.h | 2 ++
boglP.h | 2 ++
bterm.c | 36 ++++++++++++++++++++++++++----------
4 files changed, 55 insertions(+), 35 deletions(-)
diff --git a/bogl.c b/bogl.c
index 6b9996b..86bc1e0 100644
--- a/bogl.c
+++ b/bogl.c
@@ -65,6 +65,7 @@
/* Global variables. */
int bogl_xres, bogl_yres, bogl_bpp; /* bogl.h */
int bogl_refresh;
+volatile int vt_switch_pending = 0;
volatile char *bogl_frame; /* boglP.h */
int bogl_drawing;
int bogl_line_len;
@@ -120,7 +121,7 @@ static void draw_disable (void);
static void kbd_init (void);
static void kbd_done (void);
-static void vt_switch (int);
+static void sigusr2 (int);
static struct fb_fix_screeninfo fb_fix;
/* Initialize BOGL. */
@@ -181,7 +182,7 @@ bogl_init (void)
mode.relsig = SIGUSR2;
mode.acqsig = SIGUSR2;
- signal (SIGUSR2, vt_switch);
+ bogl_signal (SIGUSR2, sigusr2);
if (-1 == ioctl (tty, VT_SETMODE, &mode))
return bogl_fail ("can't set VT mode: %s", strerror (errno));
@@ -295,7 +296,7 @@ bogl_done (void)
munmap ((void *) bogl_frame, fb_fix.smem_len);
- signal (SIGUSR2, SIG_DFL);
+ bogl_signal (SIGUSR2, SIG_DFL);
ioctl (tty, KDSETMODE, KD_TEXT);
@@ -583,32 +584,18 @@ draw_disable (void)
/* Signal handler called whenever the kernel wants to switch to or
from our tty. */
static void
-vt_switch (int sig unused)
+sigusr2 (int sig unused)
{
- signal (SIGUSR2, vt_switch);
+ vt_switch_pending = 1;
+}
+void
+vt_switch (void)
+{
+ vt_switch_pending = 0;
- /* If a BOGL drawing function is in progress then we cannot mode
- switch right now because the drawing function would continue to
- scribble on the screen after the switch. So disable further
- drawing and schedule an alarm to try again in .1 second. */
if (bogl_drawing)
{
- draw_disable ();
-
- signal (SIGALRM, vt_switch);
-
- {
- struct itimerval duration;
-
- duration.it_interval.tv_sec = 0;
- duration.it_interval.tv_usec = 0;
- duration.it_value.tv_sec = 0;
- duration.it_value.tv_usec = 100000;
- if (-1 == setitimer (ITIMER_REAL, &duration, NULL))
- bogl_fail ("can't set timer: %s", strerror (errno));
- }
-
- return;
+ abort();
}
if (visible)
@@ -666,3 +653,16 @@ bogl_cloexec(int fd)
return 0;
}
+
+/* Install signal handler in a portable way (i.e. sigaction wrapper) */
+int
+bogl_signal(int signum, void (*handler) (int))
+{
+ struct sigaction sa;
+
+ sa.sa_handler = handler;
+ sigemptyset (&sa.sa_mask);
+ sa.sa_flags = SA_RESTART;
+
+ return sigaction (signum, &sa, NULL);
+}
diff --git a/bogl.h b/bogl.h
index 3b2cb83..4d99788 100644
--- a/bogl.h
+++ b/bogl.h
@@ -69,6 +69,8 @@ extern int bogl_xres, bogl_yres, bogl_ncols;
/* 1=Must refresh screen due to tty change. */
extern int bogl_refresh;
+extern volatile int vt_switch_pending;
+extern void vt_switch (void);
/* Generic routines. */
int bogl_init (void);
diff --git a/boglP.h b/boglP.h
index be99979..9a2b4aa 100644
--- a/boglP.h
+++ b/boglP.h
@@ -27,4 +27,6 @@ int bogl_fail (const char *, ...);
int bogl_cloexec (int fd);
+int bogl_signal (int signum, void (*handler) (int));
+
#endif /* boglP_h */
diff --git a/bterm.c b/bterm.c
index dfae8b9..e86a748 100644
--- a/bterm.c
+++ b/bterm.c
@@ -39,6 +39,7 @@
#include <unistd.h>
#include "bogl.h"
+#include "boglP.h"
#include "bogl-bgf.h"
#include "bogl-term.h"
@@ -160,7 +161,6 @@ void sigchld(int sig)
quit_status = status;
quit = 1;
}
- signal(SIGCHLD, sigchld);
errno = errsv;
}
@@ -176,7 +176,7 @@ void spawn_shell(int ptyfd, int ttyfd, char * const *command_args)
child_pid = fork();
if (child_pid) {
/* Change ownership and permissions of ttyfd device! */
- signal(SIGCHLD, sigchld);
+ bogl_signal(SIGCHLD, sigchld);
return;
}
@@ -212,10 +212,16 @@ void set_window_size(int ttyfd, int x, int y)
static char *font_name;
static struct bogl_term *term;
+static volatile int reload_font_pending = 0;
-void reload_font(int sig)
+void sighup(int sig)
+{
+ reload_font_pending = 1;
+}
+void reload_font(void)
{
struct bogl_font *font;
+ reload_font_pending = 0;
font = bogl_mmap_font (font_name);
if (font == NULL)
@@ -224,14 +230,14 @@ void reload_font(int sig)
return;
}
- /* BUG: Unmapping old font in this signal handler may cause crash if
- drawing is in progress, so disable this temporarily until we fix
- async-signal-safety problems completely. */
- //bogl_munmap_font(term->font);
+ bogl_munmap_font(term->font);
term->font = font;
term->xstep = bogl_font_glyph(term->font, ' ', 0);
term->ystep = bogl_font_height(term->font);
+
+ /* Request redraw */
+ bogl_refresh = 2;
}
/*
@@ -243,6 +249,7 @@ int main(int argc, char *argv[])
{
struct termios ntio;
int ret;
+ int errsv;
char buf[8192];
struct timeval tv;
int ptyfd, ttyfd;
@@ -342,8 +349,8 @@ int main(int argc, char *argv[])
}
spawn_shell(ptyfd, ttyfd, command_args);
- signal(SIGHUP, reload_font);
- signal(SIGTERM, sigterm);
+ bogl_signal(SIGHUP, sighup);
+ bogl_signal(SIGTERM, sigterm);
ntio = ttysave;
ntio.c_lflag &= ~(ECHO|ISIG|ICANON|XCASE);
@@ -363,6 +370,10 @@ int main(int argc, char *argv[])
if (quit)
break;
+ if (reload_font_pending)
+ reload_font();
+ if (vt_switch_pending)
+ vt_switch();
if(pending)
{
@@ -380,9 +391,14 @@ int main(int argc, char *argv[])
if (ptyfd > max)
max = ptyfd;
ret = select(max+1, &fds, NULL, NULL, &tv);
+ errsv = errno;
if (quit)
break;
+ if (reload_font_pending)
+ reload_font();
+ if (vt_switch_pending)
+ vt_switch();
if (bogl_refresh) {
/* Handle VT switching. */
@@ -397,7 +413,7 @@ int main(int argc, char *argv[])
bogl_refresh = 0;
bogl_term_redraw(term);
}
- if (ret == 0 || (ret < 0 && errno == EINTR))
+ if (ret == 0 || (ret < 0 && errsv == EINTR))
{
if(pending)
{
--
2.30.2
From c190ef6d7afed6539ed4de0d9e61522a72251d05 Mon Sep 17 00:00:00 2001
From: Zhang Boyang <zhangboyang...@gmail.com>
Date: Tue, 24 May 2022 23:49:31 +0800
Subject: [PATCH v5 3/4] Font scaler
Current fonts is too small to see on HiDPI displays. This patch
introduces a BGF font scaler, which can scale font glyphs on the fly
when loading. The scale factor can be automatically determined by screen
resolution or specified by a new command line argument '-s'. This patch
also adds support for BGF fonts wider than 32 pixels.
---
bogl-bgf.c | 137 ++++++++++++++++++++++++++++++++++++++++++++++++---
bogl-bgf.h | 2 +-
bogl-pcfb.c | 8 +--
bogl-tcfb.c | 8 +--
bogl-vga16.c | 33 ++++++++-----
bterm.1 | 4 ++
bterm.c | 34 ++++++++++---
7 files changed, 191 insertions(+), 35 deletions(-)
diff --git a/bogl-bgf.c b/bogl-bgf.c
index beed3c8..4cc36e2 100644
--- a/bogl-bgf.c
+++ b/bogl-bgf.c
@@ -6,12 +6,23 @@
#include <sys/types.h>
#include <unistd.h>
#include <stddef.h>
+#include <endian.h>
#include "bogl.h"
#include "boglP.h"
#include "bogl-font.h"
#include "bogl-bgf.h"
+/* Set font struct, let it point to font data in the given memory region */
+static inline void set_font(struct bogl_font *font, void *mem)
+{
+ memcpy(font, mem + 4, sizeof(*font));
+ font->name = ((void *)font->name - (void *)0) + mem;
+ font->offset = ((void *)font->offset - (void *)0) + mem;
+ font->index = ((void *)font->index - (void *)0) + mem;
+ font->content = ((void *)font->content - (void *)0) + mem;
+}
+
struct bogl_bgf {
void *f; /* mmap area */
off_t size; /* size of mmap area */
@@ -20,7 +31,122 @@ struct bogl_bgf {
#define bgf_of(font) \
((struct bogl_bgf *)((char *)(font) - offsetof(struct bogl_bgf, font)))
-struct bogl_font *bogl_mmap_font(char *file)
+/* Scale the font (both width and height)
+ Declare as inline function, will run faster if scale factor is constant */
+static inline void __attribute__((always_inline))
+bgf_scale_inline(struct bogl_bgf *bgf, int scale)
+{
+ u_int8_t *lut = NULL;
+ const u_int32_t bo = be32toh(0x00010203);
+ const u_int8_t b0 = bo >> 24, b1 = bo >> 16, b2 = bo >> 8, b3 = bo;
+ void *new_f = MAP_FAILED;
+ off_t new_size;
+ struct bogl_font new_font;
+
+ /* old_size*pow(scale,2) should enough and have some waste here */
+ new_size = bgf->size * scale * scale;
+
+ /* Allocate new memory */
+ new_f = mmap(0, new_size, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
+ if (new_f == MAP_FAILED) {
+ /* If memory allocation failed, skip scaling silently */
+ goto fail;
+ }
+
+ /* Copy old font data to new memory */
+ memcpy(new_f, bgf->f, bgf->size);
+
+ /* Set font metadata */
+ struct bogl_font *font = &new_font;
+ set_font(font, new_f);
+ font->height = bgf->font.height * scale;
+
+ /* Generate lookup table for scaling */
+ lut = calloc(0x100, scale);
+ if (!lut)
+ goto fail;
+ for (int i = 0; i < 0x100; i++)
+ for (int j = 0; j < 8 * scale; j++)
+ lut[i * scale + j / 8] |= ((i >> (7 - j / scale % 8)) & 1) << (7 - j % 8);
+
+ /* Scale each glyph */
+ int mask = font->index_mask;
+ for (int j = 0; j <= mask; j++) {
+ for (int i = font->offset[j]; font->index[i]; i += 2) {
+ int old_height = bgf->font.height;
+ int old_width = (font->index[i] & mask);
+ if (old_width * scale > mask) {
+ /* Scaled glyph width can't fit in mask, fail */
+ goto fail;
+ }
+ font->index[i] = (font->index[i] & ~mask) | (old_width * scale);
+ font->index[i + 1] *= scale * scale;
+ u_int32_t *in_bitmap = &bgf->font.content[bgf->font.index[i + 1]];
+ int in_pitch = (old_width + 31) / 32;
+ u_int32_t *out_bitmap = &font->content[font->index[i + 1]];
+ int out_pitch = (old_width * scale + 31) / 32;
+ for (int y = 0; y < old_height; y++, in_bitmap += in_pitch) {
+ u_int8_t *in_u8 = (u_int8_t *) in_bitmap;
+ u_int8_t *out_u8 = (u_int8_t *) out_bitmap;
+ /* If (in_pitch * scale) > out_pitch, this loop will overwrite next
+ scanline a little bit. Fortunately, we reserved (in_pitch * scale)
+ for each scanline, and next scanline is not processed yet, so this
+ will not cause memory errors or glyph corruption. */
+ for (int x = 0; x < in_pitch * 4; x += 4) {
+ memcpy(&out_u8[(x + 0) * scale], &lut[in_u8[x + b0] * scale], scale);
+ memcpy(&out_u8[(x + 1) * scale], &lut[in_u8[x + b1] * scale], scale);
+ memcpy(&out_u8[(x + 2) * scale], &lut[in_u8[x + b2] * scale], scale);
+ memcpy(&out_u8[(x + 3) * scale], &lut[in_u8[x + b3] * scale], scale);
+ }
+ for (int xx = 0; xx < out_pitch; xx++, out_bitmap++)
+ *out_bitmap = be32toh(*out_bitmap);
+ for (int yy = 1; yy < scale; yy++, out_bitmap += out_pitch)
+ memcpy(out_bitmap, out_u8, sizeof(u_int32_t) * out_pitch);
+ }
+ }
+ }
+
+ /* Replace old font with new font */
+ munmap(bgf->f, bgf->size);
+ bgf->f = new_f;
+ bgf->size = new_size;
+ bgf->font = new_font;
+ free(lut);
+ return;
+fail:
+ if (new_f != MAP_FAILED)
+ munmap(new_f, new_size);
+}
+static void __attribute__((noinline))
+bgf_scale_noinline(struct bogl_bgf *bgf, int scale)
+{
+ bgf_scale_inline(bgf, scale);
+}
+static void __attribute__((noinline)) bgf_scale_2x(struct bogl_bgf *bgf)
+{
+ bgf_scale_inline(bgf, 2);
+}
+static void __attribute__((noinline)) bgf_scale_4x(struct bogl_bgf *bgf)
+{
+ bgf_scale_inline(bgf, 4);
+}
+static void __attribute__((noinline)) bgf_scale_8x(struct bogl_bgf *bgf)
+{
+ bgf_scale_inline(bgf, 8);
+}
+static void bgf_scale(struct bogl_bgf *bgf, int scale)
+{
+ switch (scale) {
+ /* Use fast implementation if possible */
+ case 2: bgf_scale_2x(bgf); return;
+ case 4: bgf_scale_4x(bgf); return;
+ case 8: bgf_scale_8x(bgf); return;
+ /* Universal implementation as fallback */
+ default: bgf_scale_noinline(bgf, scale); return;
+ }
+}
+
+struct bogl_font *bogl_mmap_font(char *file, int scale)
{
struct bogl_bgf *bgf = NULL;
struct bogl_font *font = NULL;
@@ -55,11 +181,10 @@ struct bogl_font *bogl_mmap_font(char *file)
if (memcmp("BGF1", f, 4))
goto fail;
- memcpy(font, f + 4, sizeof(*font));
- font->name = ((void *)font->name - (void *)0) + f;
- font->offset = ((void *)font->offset - (void *)0) + f;
- font->index = ((void *)font->index - (void *)0) + f;
- font->content = ((void *)font->content - (void *)0) + f;
+ set_font(font, f);
+
+ if (scale >= 2)
+ bgf_scale(bgf, scale);
done:
if (fd != -1)
diff --git a/bogl-bgf.h b/bogl-bgf.h
index f14a260..978da61 100644
--- a/bogl-bgf.h
+++ b/bogl-bgf.h
@@ -1,3 +1,3 @@
-struct bogl_font *bogl_mmap_font(char *file);
+struct bogl_font *bogl_mmap_font(char *file, int scale);
void bogl_munmap_font(struct bogl_font *font);
diff --git a/bogl-pcfb.c b/bogl-pcfb.c
index c737d38..b16c804 100644
--- a/bogl-pcfb.c
+++ b/bogl-pcfb.c
@@ -142,6 +142,7 @@ bogl_pcfb_text (int xx, int yy, const char *s, int n, int fg, int bg, int ul,
u_int32_t *character = NULL;
int w = bogl_font_glyph (font, wc, &character);
+ int pitch = (w + 31) / 32;
int x, y, h1 = ul ? h - 1 : h;
@@ -153,16 +154,15 @@ bogl_pcfb_text (int xx, int yy, const char *s, int n, int fg, int bg, int ul,
for (y = 0; y < h1; y++)
{
- u_int32_t c = *character++;
+ u_int32_t *c = character;
+ character += pitch;
for (x = 0; x < w; x++)
{
- if (c & 0x80000000)
+ if ((c[x / 32] & (1 << (31 - x % 32))))
put_var (dst, xx+x, cmap_lookup(fg), bpp);
else if (bg != -1)
put_var (dst, xx+x, cmap_lookup(bg), bpp);
-
- c <<= 1;
}
dst += bogl_line_len;
diff --git a/bogl-tcfb.c b/bogl-tcfb.c
index 76f44da..5e14892 100644
--- a/bogl-tcfb.c
+++ b/bogl-tcfb.c
@@ -169,6 +169,7 @@ bogl_tcfb_text (int xx, int yy, const char *s, int n, int fg, int bg, int ul,
u_int32_t *character = NULL;
int w = bogl_font_glyph (font, wc, &character);
+ int pitch = (w + 31) / 32;
int x, y, h1 = ul ? h - 1 : h;
unsigned cfg = cmap_lookup (fg), cbg = cmap_lookup (bg);
@@ -181,16 +182,15 @@ bogl_tcfb_text (int xx, int yy, const char *s, int n, int fg, int bg, int ul,
for (y = 0; y < h1; y++)
{
- u_int32_t c = *character++;
+ u_int32_t *c = character;
+ character += pitch;
for (x = 0; x < w; x++)
{
- if (c & 0x80000000)
+ if ((c[x / 32] & (1 << (31 - x % 32))))
put_var (dst, xx+x, cfg, bpp);
else if (bg != -1)
put_var (dst, xx+x, cbg, bpp);
-
- c <<= 1;
}
dst += bogl_line_len;
diff --git a/bogl-vga16.c b/bogl-vga16.c
index 6e7f0b0..3fcbe51 100644
--- a/bogl-vga16.c
+++ b/bogl-vga16.c
@@ -394,25 +394,34 @@ bogl_vga16_text (int xx, int yy, const char *s, int n, int fg, int bg, int ul,
{
u_int32_t *character = NULL;
int width = bogl_font_glyph (font, wc, &character);
+ int pitch = (width + ul_bits - 1) / ul_bits;
if (character == NULL)
continue;
- for (y = 0; y < h; y++)
- bits[y] |= character[y] >> x;
- x += width;
-
- if (x >= (int) ul_bits)
- {
- plot (bg);
+ int i, w;
+ for (i = 0; i < pitch; i++)
+ {
+ w = width - i * ul_bits;
+ if (w > ul_bits)
+ w = ul_bits;
- x -= ul_bits;
for (y = 0; y < h; y++)
- bits[y] = character[y] << (width - x);
+ bits[y] |= character[y * pitch + i] >> x;
+ x += w;
- xx += ul_bits;
- if (xx >= bogl_xres)
- goto done;
+ if (x >= (int) ul_bits)
+ {
+ plot (bg);
+
+ x -= ul_bits;
+ for (y = 0; y < h; y++)
+ bits[y] = character[y * pitch + i] << (w - x - 1) << 1;
+
+ xx += ul_bits;
+ if (xx >= bogl_xres)
+ goto done;
+ }
}
}
plot (bg);
diff --git a/bterm.1 b/bterm.1
index 8b96b99..e62d3ee 100644
--- a/bterm.1
+++ b/bterm.1
@@ -21,6 +21,7 @@ bterm - framebuffer terminal emulator
.B bterm
.B -f
.RI font.bgf
+.RI "[-s " scale "]"
.RI "[-l " locale "]"
.RI "[" program "]"
.SH DESCRIPTION
@@ -36,6 +37,9 @@ Specify the font. BGF fonts are produced by
.BR bdftobogl (1)
from standard BDF font files.
.TP
+.B -s scale
+Specify the font scale factor, 0 for auto.
+.TP
.B -l locale
Specify a locale for
.B bterm
diff --git a/bterm.c b/bterm.c
index e86a748..b552b6e 100644
--- a/bterm.c
+++ b/bterm.c
@@ -211,6 +211,7 @@ void set_window_size(int ttyfd, int x, int y)
}
static char *font_name;
+static int font_scale;
static struct bogl_term *term;
static volatile int reload_font_pending = 0;
@@ -223,7 +224,7 @@ void reload_font(void)
struct bogl_font *font;
reload_font_pending = 0;
- font = bogl_mmap_font (font_name);
+ font = bogl_mmap_font (font_name, font_scale);
if (font == NULL)
{
fprintf(stderr, "Bad font\n");
@@ -242,7 +243,7 @@ void reload_font(void)
/*
* The usage is very simple:
- * bterm -f font.bgf [ -l locale ] [ program ]
+ * bterm -f font.bgf [ -s scale ] [ -l locale ] [ program ]
*/
int main(int argc, char *argv[])
@@ -266,6 +267,7 @@ int main(int argc, char *argv[])
switch (argv[i][1])
{
case 'f':
+ case 's':
case 'l':
o = argv[i][1];
break;
@@ -289,6 +291,11 @@ int main(int argc, char *argv[])
o = ' ';
break;
+ case 's':
+ font_scale = atoi(argv[i]);
+ o = ' ';
+ break;
+
case 'l':
locale = argv[i];
o = ' ';
@@ -302,16 +309,11 @@ int main(int argc, char *argv[])
setlocale(LC_CTYPE, locale);
if (font_name == NULL) {
- fprintf(stderr, "Usage: %s -f font.bgf [ -l locale ] [ program ]\n", argv[0]);
+ fprintf(stderr, "Usage: %s -f font.bgf [ -s scale ] [ -l locale ] [ program ]\n", argv[0]);
return 1;
}
- if ((font = bogl_mmap_font(font_name)) == NULL) {
- fprintf(stderr, "Bad font\n");
- return 1;
- }
-
tcgetattr(0, &ttysave);
if (!bogl_init()) {
@@ -319,6 +321,22 @@ int main(int argc, char *argv[])
return 1;
}
+ if (font_scale == 0) {
+ if (bogl_xres > 7680 && bogl_yres > 4320)
+ font_scale = 8;
+ else if (bogl_xres > 3840 && bogl_yres > 2160)
+ font_scale = 4;
+ else if (bogl_xres > 1920 && bogl_yres > 1080)
+ font_scale = 2;
+ else
+ font_scale = 1;
+ }
+
+ if ((font = bogl_mmap_font(font_name, font_scale)) == NULL) {
+ fprintf(stderr, "Bad font\n");
+ return 1;
+ }
+
term = bogl_term_new(font);
if (!term)
exit(1);
--
2.30.2
