txtwin.c

   1 #include <ctype.h>
   2 #include <errno.h>
   3 #include <fcntl.h>
   4 #include <locale.h>
   5 #include <poll.h>
   6 #include <stdio.h>
   7 #include <stdlib.h>
   8 #include <string.h>
   9 #include <sys/wait.h>
  10 #include <unistd.h>
  11 #include <pty.h>
  12
  13 #include <glib.h>
  14 #include <pango/pango.h>
  15 #include <pango/pangoft2.h>
  16
  17 #include "draw.h"
  18 #include "config.h"
  19
  20 #define MAXTEXT                 (1 << 20)
  21 #define MAXLINE                 ((MAXTEXT) >> 4)
  22 #define DPI                     196
  23 #define PAGESTEPS               8
  24 #define CTRLKEY(x)              ((x) - 96)
  25
  26 #define CR(a)                   (((a) >> 16) & 0xff)
  27 #define CG(a)                   (((a) >> 8) & 0xff)
  28 #define CB(a)                   ((a) & 0xff)
  29 #define COLORMERGE(f, b, c)     ((b) + (((f) - (b)) * (c) >> 8u))
  30
  31 static PangoContext *context;
  32 static PangoFontMap *fontmap;
  33 static FT_Bitmap *bitmap;
  34 static char name[128];          /* sura name */
  35 static int pcols = 1;           /* bitmap width */
  36 static int prows = 1;           /* bitmap height */
  37 static int head;
  38 static char text[MAXTEXT];
  39 static char *pos = text;
  40 static int pos_off;
  41 static int count;
  42 static int mark[256];
  43 static int lnpos[MAXLINE];      /* line offsets as reported by txtwin_line() */
  44 static int lnrow[MAXLINE];      /* line row in the layout */
  45 static int nlnpos;
  46
  47 static void draw(int sr)
  48 {
  49         int r, c;
  50         fbval_t buf[1 << 14];
  51         int nr = MIN(prows - sr, fb_rows());
  52         int nc = MIN(pcols, fb_cols());
  53         for (r = 0; r < nr; r++) {
  54                 for (c = 0; c < nc; c++) {
  55                         int v = bitmap->buffer[(sr + r) * bitmap->pitch + c];
  56                         int r = COLORMERGE(CR(COLOR_FG), CR(COLOR_BG), v);
  57                         int g = COLORMERGE(CG(COLOR_FG), CG(COLOR_BG), v);
  58                         int b = COLORMERGE(CB(COLOR_FG), CB(COLOR_BG), v);
  59                         buf[c] = FB_VAL(r, g, b);
  60                 }
  61                 fb_set(r, 0, buf, pcols);
  62         }
  63 }
  64
  65 static FT_Bitmap *create_bitmap(int pcols, int prows)
  66 {
  67         FT_Bitmap *bitmap = g_slice_new(FT_Bitmap);
  68         bitmap->width = pcols;
  69         bitmap->pitch = (bitmap->width + 3) & ~3;
  70         bitmap->rows = prows;
  71         bitmap->buffer = g_malloc(bitmap->pitch * bitmap->rows);
  72         bitmap->num_grays = 256;
  73         bitmap->pixel_mode = ft_pixel_mode_grays;
  74         memset(bitmap->buffer, 0, bitmap->pitch * bitmap->rows);
  75         return bitmap;
  76 }
  77
  78 static void destroy_bitmap(FT_Bitmap *bitmap)
  79 {
  80         g_free(bitmap->buffer);
  81         g_slice_free(FT_Bitmap, bitmap);
  82 }
  83
  84 static PangoLayout *make_layout(PangoContext *context, char *text, double size)
  85 {
  86         static PangoFontDescription *font_description;
  87         PangoLayout *layout = pango_layout_new(context);
  88         pango_layout_set_markup(layout, text, -1);
  89         pango_layout_set_wrap(layout, PANGO_WRAP_WORD_CHAR);
  90         pango_layout_set_width(layout, fb_cols() << 10);
  91         pango_layout_set_height(layout, -1);
  92         pango_layout_set_alignment(layout, PANGO_ALIGN_RIGHT);
  93         pango_layout_set_font_description(layout, font_description);
  94         pango_font_description_free(font_description);
  95         return layout;
  96 }
  97
  98 static void do_output(PangoContext *context, char *text)
  99 {
 100         PangoLayout *layout;
 101         PangoRectangle rect;
 102         int i;
 103         pango_context_set_language(context, pango_language_get_default());
 104         pango_context_set_base_dir(context, PANGO_DIRECTION_RTL);
 105         layout = make_layout(context, text, -1);
 106         pango_layout_get_pixel_extents(layout, NULL, &rect);
 107         pango_ft2_render_layout(bitmap, layout, 0, 0);
 108         pcols = MAX(pcols, MAX(rect.x + rect.width,
 109                         PANGO_PIXELS(pango_layout_get_width(layout))));
 110         prows = MAX(rect.y + rect.height,
 111                 PANGO_PIXELS(pango_layout_get_height(layout)));
 112         for (i = 0; i < nlnpos; i++) {
 113                 pango_layout_index_to_pos(layout, lnpos[i], &rect);
 114                 lnrow[i] = PANGO_PIXELS(rect.y);
 115         }
 116         g_object_unref(layout);
 117 }
 118
 119 static int readkey(void)
 120 {
 121         char b;
 122         if (read(0, &b, 1) <= 0)
 123                 return -1;
 124         return (unsigned char) b;
 125 }
 126
 127 void txtwin_append(char *s, char *font)
 128 {
 129         snprintf(pos, MAXTEXT - (pos - text),
 130                  "<span font=\"%s\">%s</span>", font, s);
 131         pos = strchr(pos, '\0');
 132         pos_off += strlen(s);
 133 }
 134
 135 void txtwin_line(void)
 136 {
 137         lnpos[nlnpos++] = pos_off;
 138 }
 139
 140 static int getcount(int def)
 141 {
 142         int result = count ? count : def;
 143         count = 0;
 144         return result;
 145 }
 146
 147 static void printinfo(void)
 148 {
 149         printf("\x1b[H");
 150         printf("CNOOR \t\t\t %d%% \t\t\t %s \x1b[K", head * 100 / prows, name);
 151         fflush(stdout);
 152 }
 153
 154 static void scroll(int h)
 155 {
 156         mark['\''] = head;
 157         head = MAX(0, MIN(h, prows - fb_rows()));
 158 }
 159
 160 static void scroll_rel(int diff)
 161 {
 162         head = MAX(0, MIN(head + diff, prows - fb_rows()));
 163 }
 164
 165 void txtwin_loop(void)
 166 {
 167         int step = fb_rows() / PAGESTEPS;
 168         struct termios oldtermios, termios;
 169         int c, i;
 170         tcgetattr(0, &termios);
 171         oldtermios = termios;
 172         cfmakeraw(&termios);
 173         tcsetattr(0, TCSAFLUSH, &termios);
 174         bitmap = create_bitmap(pcols, prows);
 175         do_output(context, text);
 176         destroy_bitmap(bitmap);
 177         bitmap = create_bitmap(pcols, prows);
 178         do_output(context, text);
 179         draw(head);
 180         while ((c = readkey()) >= 0) {
 181                 switch (c) {
 182                 case 27:
 183                         count = 0;
 184                         break;
 185                 case 'q':
 186                         tcsetattr(0, 0, &oldtermios);
 187                         return;
 188                 default:
 189                         if (isdigit(c))
 190                                 count = count * 10 + c - '0';
 191                 }
 192                 switch (c) {
 193                 case 'j':
 194                         scroll_rel(+step * getcount(1));
 195                         break;
 196                 case 'k':
 197                         scroll_rel(-step * getcount(1));
 198                         break;
 199                 case CTRLKEY('f'):
 200                 case ' ':
 201                         scroll_rel(+fb_rows() * getcount(1) - step);
 202                         break;
 203                 case CTRLKEY('b'):
 204                 case 127:
 205                         scroll_rel(-fb_rows() * getcount(1) + step);
 206                         break;
 207                 case CTRLKEY('l'):
 208                         break;
 209                 case 'G':
 210                         i = getcount(0);
 211                         if (i > 0 && i < nlnpos)
 212                                 scroll(MIN(lnrow[i - 1], prows - fb_rows()));
 213                         else
 214                                 scroll(prows - fb_rows());
 215                         break;
 216                 case '%':
 217                         if (count)
 218                                 scroll(prows * getcount(0) / 100);
 219                         break;
 220                 case 'i':
 221                         printinfo();
 222                         continue;
 223                 case 'm':
 224                         mark[readkey()] = head;
 225                         continue;
 226                 case '\'':
 227                         c = readkey();
 228                         if (mark[c] >= 0)
 229                                 scroll(mark[c]);
 230                         break;
 231                 default:
 232                         /* no need to redraw */
 233                         continue;
 234                 }
 235                 draw(head);
 236         }
 237 }
 238
 239 void txtwin_init(char *sura)
 240 {
 241         setlocale(LC_ALL, "");
 242         g_set_prgname("cnoor");
 243         fontmap = pango_ft2_font_map_new();
 244         pango_ft2_font_map_set_resolution(PANGO_FT2_FONT_MAP(fontmap), DPI, DPI);
 245         context = pango_font_map_create_context(PANGO_FONT_MAP(fontmap));
 246         strcpy(name, sura);
 247         if (fb_init())
 248                 exit(1);
 249         if (FBM_BPP(fb_mode()) != sizeof(fbval_t)) {
 250                 fprintf(stderr, "cnoor: fbval_t doesn't match fb depth\n");
 251                 exit(1);
 252         }
 253         printf("\x1b[2J\x1b[H\x1b[?25l");
 254         printinfo();
 255         memset(mark, 0xff, sizeof(mark));
 256 }
 257
 258 void txtwin_free(void)
 259 {
 260         fb_free();
 261         destroy_bitmap(bitmap);
 262         g_object_unref(context);
 263         g_object_unref(fontmap);
 264         printf("\x1b[?25h\n");
 265 }