ip: use rtnl_send_check() on flush commands, closes 6962
[oweals/busybox.git] / util-linux / fbset.c
index 69986df256e4398e8fbf9ee622675d69a359f144..699a19372474e87954a2c3a6fa787b5f6d028e72 100644 (file)
@@ -4,64 +4,65 @@
  *
  * Copyright (C) 1999 by Randolph Chung <tausq@debian.org>
  *
- * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
+ * Licensed under GPLv2 or later, see file LICENSE in this source tree.
  *
  * This is a from-scratch implementation of fbset; but the de facto fbset
  * implementation was a good reference. fbset (original) is released under
  * the GPL, and is (c) 1995-1999 by:
  *     Geert Uytterhoeven (Geert.Uytterhoeven@cs.kuleuven.ac.be)
  */
+//config:config FBSET
+//config:      bool "fbset (5.9 kb)"
+//config:      default y
+//config:      select PLATFORM_LINUX
+//config:      help
+//config:      fbset is used to show or change the settings of a Linux frame buffer
+//config:      device. The frame buffer device provides a simple and unique
+//config:      interface to access a graphics display. Enable this option
+//config:      if you wish to enable the 'fbset' utility.
+//config:
+//config:config FEATURE_FBSET_FANCY
+//config:      bool "Enable extra options"
+//config:      default y
+//config:      depends on FBSET
+//config:      help
+//config:      This option enables extended fbset options, allowing one to set the
+//config:      framebuffer size, color depth, etc. interface to access a graphics
+//config:      display. Enable this option if you wish to enable extended fbset
+//config:      options.
+//config:
+//config:config FEATURE_FBSET_READMODE
+//config:      bool "Enable readmode support"
+//config:      default y
+//config:      depends on FBSET
+//config:      help
+//config:      This option allows fbset to read the video mode database stored by
+//config:      default as /etc/fb.modes, which can be used to set frame buffer
+//config:      device to pre-defined video modes.
 
-#include "libbb.h"
+//applet:IF_FBSET(APPLET(fbset, BB_DIR_USR_SBIN, BB_SUID_DROP))
 
-#define DEFAULTFBDEV  FB_0
-#define DEFAULTFBMODE "/etc/fb.modes"
-
-enum {
-       OPT_CHANGE   = (1 << 0),
-       OPT_INFO     = (1 << 1),
-       OPT_READMODE = (1 << 2),
-       OPT_ALL      = (1 << 9),
+//kbuild:lib-$(CONFIG_FBSET) += fbset.o
 
-       CMD_FB = 1,
-       CMD_DB = 2,
-       CMD_GEOMETRY = 3,
-       CMD_TIMING = 4,
-       CMD_ACCEL = 5,
-       CMD_HSYNC = 6,
-       CMD_VSYNC = 7,
-       CMD_LACED = 8,
-       CMD_DOUBLE = 9,
-/*     CMD_XCOMPAT =     10, */
-       CMD_ALL = 11,
-       CMD_INFO = 12,
-       CMD_CHANGE = 13,
+//usage:#define fbset_trivial_usage
+//usage:       "[OPTIONS] [MODE]"
+//usage:#define fbset_full_usage "\n\n"
+//usage:       "Show and modify frame buffer settings"
+//usage:
+//usage:#define fbset_example_usage
+//usage:       "$ fbset\n"
+//usage:       "mode \"1024x768-76\"\n"
+//usage:       "       # D: 78.653 MHz, H: 59.949 kHz, V: 75.694 Hz\n"
+//usage:       "       geometry 1024 768 1024 768 16\n"
+//usage:       "       timings 12714 128 32 16 4 128 4\n"
+//usage:       "       accel false\n"
+//usage:       "       rgba 5/11,6/5,5/0,0/0\n"
+//usage:       "endmode\n"
 
-#ifdef CONFIG_FEATURE_FBSET_FANCY
-       CMD_XRES = 100,
-       CMD_YRES = 101,
-       CMD_VXRES = 102,
-       CMD_VYRES = 103,
-       CMD_DEPTH = 104,
-       CMD_MATCH = 105,
-       CMD_PIXCLOCK = 106,
-       CMD_LEFT = 107,
-       CMD_RIGHT = 108,
-       CMD_UPPER = 109,
-       CMD_LOWER = 110,
-       CMD_HSLEN = 111,
-       CMD_VSLEN = 112,
-       CMD_CSYNC = 113,
-       CMD_GSYNC = 114,
-       CMD_EXTSYNC = 115,
-       CMD_BCAST = 116,
-       CMD_RGBA = 117,
-       CMD_STEP = 118,
-       CMD_MOVE = 119,
-#endif
-};
+#include "libbb.h"
 
-static unsigned g_options;
+#define DEFAULTFBDEV  FB_0
+#define DEFAULTFBMODE "/etc/fb.modes"
 
 /* Stuff stolen from the kernel's fb.h */
 #define FB_ACTIVATE_ALL 64
@@ -69,9 +70,10 @@ enum {
        FBIOGET_VSCREENINFO = 0x4600,
        FBIOPUT_VSCREENINFO = 0x4601
 };
+
 struct fb_bitfield {
        uint32_t offset;                /* beginning of bitfield */
-       uint32_t length;                /* length of bitfield */
+       uint32_t length;                /* length of bitfield */
        uint32_t msb_right;             /* !=0: Most significant bit is right */
 };
 struct fb_var_screeninfo {
@@ -97,7 +99,7 @@ struct fb_var_screeninfo {
        uint32_t height;                /* height of picture in mm */
        uint32_t width;                 /* width of picture in mm */
 
-       uint32_t accel_flags;           /* acceleration flags (hints)   */
+       uint32_t accel_flags;           /* acceleration flags (hints) */
 
        /* Timing: All values in pixclocks, except pixclock (of course) */
        uint32_t pixclock;              /* pixel clock in ps (pico seconds) */
@@ -112,171 +114,298 @@ struct fb_var_screeninfo {
        uint32_t reserved[6];           /* Reserved for future compatibility */
 };
 
+static void copy_if_gt0(uint32_t *src, uint32_t *dst, unsigned cnt)
+{
+       do {
+               if ((int32_t) *src > 0)
+                       *dst = *src;
+               src++;
+               dst++;
+       } while (--cnt);
+}
+
+static NOINLINE void copy_changed_values(
+               struct fb_var_screeninfo *base,
+               struct fb_var_screeninfo *set)
+{
+       //if ((int32_t) set->xres > 0) base->xres = set->xres;
+       //if ((int32_t) set->yres > 0) base->yres = set->yres;
+       //if ((int32_t) set->xres_virtual > 0)   base->xres_virtual = set->xres_virtual;
+       //if ((int32_t) set->yres_virtual > 0)   base->yres_virtual = set->yres_virtual;
+       copy_if_gt0(&set->xres, &base->xres, 4);
+
+       if ((int32_t) set->bits_per_pixel > 0) base->bits_per_pixel = set->bits_per_pixel;
+       //copy_if_gt0(&set->bits_per_pixel, &base->bits_per_pixel, 1);
+
+       //if ((int32_t) set->pixclock > 0)       base->pixclock = set->pixclock;
+       //if ((int32_t) set->left_margin > 0)    base->left_margin = set->left_margin;
+       //if ((int32_t) set->right_margin > 0)   base->right_margin = set->right_margin;
+       //if ((int32_t) set->upper_margin > 0)   base->upper_margin = set->upper_margin;
+       //if ((int32_t) set->lower_margin > 0)   base->lower_margin = set->lower_margin;
+       //if ((int32_t) set->hsync_len > 0) base->hsync_len = set->hsync_len;
+       //if ((int32_t) set->vsync_len > 0) base->vsync_len = set->vsync_len;
+       //if ((int32_t) set->sync > 0)  base->sync = set->sync;
+       //if ((int32_t) set->vmode > 0) base->vmode = set->vmode;
+       copy_if_gt0(&set->pixclock, &base->pixclock, 9);
+}
+
+
+enum {
+       CMD_FB = 1,
+       CMD_DB = 2,
+       CMD_GEOMETRY = 3,
+       CMD_TIMING = 4,
+       CMD_ACCEL = 5,
+       CMD_HSYNC = 6,
+       CMD_VSYNC = 7,
+       CMD_LACED = 8,
+       CMD_DOUBLE = 9,
+/*     CMD_XCOMPAT =     10, */
+       CMD_ALL = 11,
+       CMD_INFO = 12,
+       CMD_SHOW = 13,
+       CMD_CHANGE = 14,
+
+#if ENABLE_FEATURE_FBSET_FANCY
+       CMD_XRES = 100,
+       CMD_YRES = 101,
+       CMD_VXRES = 102,
+       CMD_VYRES = 103,
+       CMD_DEPTH = 104,
+       CMD_MATCH = 105,
+       CMD_PIXCLOCK = 106,
+       CMD_LEFT = 107,
+       CMD_RIGHT = 108,
+       CMD_UPPER = 109,
+       CMD_LOWER = 110,
+       CMD_HSLEN = 111,
+       CMD_VSLEN = 112,
+       CMD_CSYNC = 113,
+       CMD_GSYNC = 114,
+       CMD_EXTSYNC = 115,
+       CMD_BCAST = 116,
+       CMD_RGBA = 117,
+       CMD_STEP = 118,
+       CMD_MOVE = 119,
+#endif
+};
 
 static const struct cmdoptions_t {
-       const char name[10];
+       const char name[9];
        const unsigned char param_count;
        const unsigned char code;
 } g_cmdoptions[] = {
-       { "-fb", 1, CMD_FB },
-       { "-db", 1, CMD_DB },
-       { "-a", 0, CMD_ALL },
-       { "-i", 0, CMD_INFO },
-       { "-g", 5, CMD_GEOMETRY },
-       { "-t", 7, CMD_TIMING },
-       { "-accel", 1, CMD_ACCEL },
-       { "-hsync", 1, CMD_HSYNC },
-       { "-vsync", 1, CMD_VSYNC },
-       { "-laced", 1, CMD_LACED },
-       { "-double", 1, CMD_DOUBLE },
-       { "-n", 0, CMD_CHANGE },
-#ifdef CONFIG_FEATURE_FBSET_FANCY
-       { "-all", 0, CMD_ALL },
-       { "-xres", 1, CMD_XRES },
-       { "-yres", 1, CMD_YRES },
-       { "-vxres", 1, CMD_VXRES },
-       { "-vyres", 1, CMD_VYRES },
-       { "-depth", 1, CMD_DEPTH },
-       { "-match", 0, CMD_MATCH },
-       { "-geometry", 5, CMD_GEOMETRY },
-       { "-pixclock", 1, CMD_PIXCLOCK },
-       { "-left", 1, CMD_LEFT },
-       { "-right", 1, CMD_RIGHT },
-       { "-upper", 1, CMD_UPPER },
-       { "-lower", 1, CMD_LOWER },
-       { "-hslen", 1, CMD_HSLEN },
-       { "-vslen", 1, CMD_VSLEN },
-       { "-timings", 7, CMD_TIMING },
-       { "-csync", 1, CMD_CSYNC },
-       { "-gsync", 1, CMD_GSYNC },
-       { "-extsync", 1, CMD_EXTSYNC },
-       { "-bcast", 1, CMD_BCAST },
-       { "-rgba", 1, CMD_RGBA },
-       { "-step", 1, CMD_STEP },
-       { "-move", 1, CMD_MOVE },
+       /*"12345678" + NUL */
+//TODO: convert to index_in_strings()
+       { "fb"      , 1, CMD_FB       },
+       { "db"      , 1, CMD_DB       },
+       { "a"       , 0, CMD_ALL      },
+       { "i"       , 0, CMD_INFO     },
+       { "g"       , 5, CMD_GEOMETRY },
+       { "t"       , 7, CMD_TIMING   },
+       { "accel"   , 1, CMD_ACCEL    },
+       { "hsync"   , 1, CMD_HSYNC    },
+       { "vsync"   , 1, CMD_VSYNC    },
+       { "laced"   , 1, CMD_LACED    },
+       { "double"  , 1, CMD_DOUBLE   },
+       { "show"    , 0, CMD_SHOW     },
+       { "s"       , 0, CMD_SHOW     },
+#if ENABLE_FEATURE_FBSET_FANCY
+       { "all"     , 0, CMD_ALL      },
+       { "xres"    , 1, CMD_XRES     },
+       { "yres"    , 1, CMD_YRES     },
+       { "vxres"   , 1, CMD_VXRES    },
+       { "vyres"   , 1, CMD_VYRES    },
+       { "depth"   , 1, CMD_DEPTH    },
+       { "match"   , 0, CMD_MATCH    },
+       { "geometry", 5, CMD_GEOMETRY },
+       { "pixclock", 1, CMD_PIXCLOCK },
+       { "left"    , 1, CMD_LEFT     },
+       { "right"   , 1, CMD_RIGHT    },
+       { "upper"   , 1, CMD_UPPER    },
+       { "lower"   , 1, CMD_LOWER    },
+       { "hslen"   , 1, CMD_HSLEN    },
+       { "vslen"   , 1, CMD_VSLEN    },
+       { "timings" , 7, CMD_TIMING   },
+       { "csync"   , 1, CMD_CSYNC    },
+       { "gsync"   , 1, CMD_GSYNC    },
+       { "extsync" , 1, CMD_EXTSYNC  },
+       { "bcast"   , 1, CMD_BCAST    },
+       { "rgba"    , 1, CMD_RGBA     },
+       { "step"    , 1, CMD_STEP     },
+       { "move"    , 1, CMD_MOVE     },
 #endif
-       { "", 0, 0 }
 };
 
-#ifdef CONFIG_FEATURE_FBSET_READMODE
 /* taken from linux/fb.h */
 enum {
-       FB_VMODE_INTERLACED = 1,        /* interlaced   */
-       FB_VMODE_DOUBLE = 2,    /* double scan */
-       FB_SYNC_HOR_HIGH_ACT = 1,       /* horizontal sync high active  */
-       FB_SYNC_VERT_HIGH_ACT = 2,      /* vertical sync high active    */
-       FB_SYNC_EXT = 4,        /* external sync                */
-       FB_SYNC_COMP_HIGH_ACT = 8       /* composite sync high active   */
-};
+       FB_SYNC_HOR_HIGH_ACT = 1,       /* horizontal sync high active */
+       FB_SYNC_VERT_HIGH_ACT = 2,      /* vertical sync high active */
+#if ENABLE_FEATURE_FBSET_READMODE
+       FB_VMODE_INTERLACED = 1,        /* interlaced */
+       FB_VMODE_DOUBLE = 2,            /* double scan */
+       FB_SYNC_EXT = 4,                /* external sync */
+       FB_SYNC_COMP_HIGH_ACT = 8,      /* composite sync high active */
 #endif
+};
+
+#if ENABLE_FEATURE_FBSET_READMODE
+static void ss(uint32_t *x, uint32_t flag, char *buf, const char *what)
+{
+       if (strcmp(buf, what) == 0)
+               *x &= ~flag;
+       else
+               *x |= flag;
+}
 
-static int readmode(struct fb_var_screeninfo *base, const char *fn,
+/* Mode db file contains mode definitions like this:
+ * mode "800x600-48-lace"
+ *     # D: 36.00 MHz, H: 33.835 kHz, V: 96.39 Hz
+ *     geometry 800 600 800 600 8
+ *     timings 27778 56 80 79 11 128 12
+ *     laced true
+ *     hsync high
+ *     vsync high
+ * endmode
+ */
+static int read_mode_db(struct fb_var_screeninfo *base, const char *fn,
                                        const char *mode)
 {
-#ifdef CONFIG_FEATURE_FBSET_READMODE
-       FILE *f;
-       char buf[256];
-       char *p = buf;
-
-       f = xfopen(fn, "r");
-       while (!feof(f)) {
-               fgets(buf, sizeof(buf), f);
-               if (!(p = strstr(buf, "mode ")) && !(p = strstr(buf, "mode\t")))
+       char *token[2], *p, *s;
+       parser_t *parser = config_open(fn);
+
+       while (config_read(parser, token, 2, 1, "# \t\r", PARSE_NORMAL)) {
+               if (strcmp(token[0], "mode") != 0 || !token[1])
                        continue;
-               p += 5;
-               if (!(p = strstr(buf, mode)))
+               p = strstr(token[1], mode);
+               if (!p)
                        continue;
-               p += strlen(mode);
-               if (!isspace(*p) && (*p != 0) && (*p != '"')
-                               && (*p != '\r') && (*p != '\n'))
-                       continue;       /* almost, but not quite */
-
-               while (!feof(f)) {
-                       fgets(buf, sizeof(buf), f);
-                       if ((p = strstr(buf, "geometry "))) {
-                               p += 9;
-                               /* FIXME: catastrophic on arches with 64bit ints */
+               s = p + strlen(mode);
+               //bb_error_msg("CHECK[%s][%s][%d]", mode, p-1, *s);
+               /* exact match? */
+               if (((!*s || isspace(*s)) && '"' != s[-1]) /* end-of-token */
+                || ('"' == *s && '"' == p[-1]) /* ends with " but starts with " too! */
+               ) {
+                       //bb_error_msg("FOUND[%s][%s][%s][%d]", token[1], p, mode, isspace(*s));
+                       break;
+               }
+       }
+
+       if (!token[0])
+               return 0;
+
+       while (config_read(parser, token, 2, 1, "# \t", PARSE_NORMAL)) {
+               int i;
+
+//bb_error_msg("???[%s][%s]", token[0], token[1]);
+               if (strcmp(token[0], "endmode") == 0) {
+//bb_error_msg("OK[%s]", mode);
+                       return 1;
+               }
+               p = token[1];
+               i = index_in_strings(
+                       "geometry\0timings\0interlaced\0double\0vsync\0hsync\0csync\0extsync\0rgba\0",
+                       token[0]);
+               switch (i) {
+               case 0:
+                       if (sizeof(int) == sizeof(base->xres)) {
+                               sscanf(p, "%d %d %d %d %d",
+                                       &base->xres, &base->yres,
+                                       &base->xres_virtual, &base->yres_virtual,
+                                       &base->bits_per_pixel);
+                       } else {
+                               int base_xres, base_yres;
+                               int base_xres_virtual, base_yres_virtual;
+                               int base_bits_per_pixel;
                                sscanf(p, "%d %d %d %d %d",
-                                       &(base->xres), &(base->yres),
-                                       &(base->xres_virtual), &(base->yres_virtual),
-                                       &(base->bits_per_pixel));
-                       } else if ((p = strstr(buf, "timings "))) {
-                               p += 8;
+                                       &base_xres, &base_yres,
+                                       &base_xres_virtual, &base_yres_virtual,
+                                       &base_bits_per_pixel);
+                               base->xres = base_xres;
+                               base->yres = base_yres;
+                               base->xres_virtual = base_xres_virtual;
+                               base->yres_virtual = base_yres_virtual;
+                               base->bits_per_pixel = base_bits_per_pixel;
+                       }
+//bb_error_msg("GEO[%s]", p);
+                       break;
+               case 1:
+                       if (sizeof(int) == sizeof(base->xres)) {
                                sscanf(p, "%d %d %d %d %d %d %d",
-                                       &(base->pixclock),
-                                       &(base->left_margin), &(base->right_margin),
-                                       &(base->upper_margin), &(base->lower_margin),
-                                       &(base->hsync_len), &(base->vsync_len));
-                       } else if ((p = strstr(buf, "laced "))) {
-                               //p += 6;
-                               if (strstr(buf, "false")) {
-                                       base->vmode &= ~FB_VMODE_INTERLACED;
-                               } else {
-                                       base->vmode |= FB_VMODE_INTERLACED;
-                               }
-                       } else if ((p = strstr(buf, "double "))) {
-                               //p += 7;
-                               if (strstr(buf, "false")) {
-                                       base->vmode &= ~FB_VMODE_DOUBLE;
-                               } else {
-                                       base->vmode |= FB_VMODE_DOUBLE;
-                               }
-                       } else if ((p = strstr(buf, "vsync "))) {
-                               //p += 6;
-                               if (strstr(buf, "low")) {
-                                       base->sync &= ~FB_SYNC_VERT_HIGH_ACT;
-                               } else {
-                                       base->sync |= FB_SYNC_VERT_HIGH_ACT;
-                               }
-                       } else if ((p = strstr(buf, "hsync "))) {
-                               //p += 6;
-                               if (strstr(buf, "low")) {
-                                       base->sync &= ~FB_SYNC_HOR_HIGH_ACT;
-                               } else {
-                                       base->sync |= FB_SYNC_HOR_HIGH_ACT;
-                               }
-                       } else if ((p = strstr(buf, "csync "))) {
-                               //p += 6;
-                               if (strstr(buf, "low")) {
-                                       base->sync &= ~FB_SYNC_COMP_HIGH_ACT;
-                               } else {
-                                       base->sync |= FB_SYNC_COMP_HIGH_ACT;
-                               }
-                       } else if ((p = strstr(buf, "extsync "))) {
-                               //p += 8;
-                               if (strstr(buf, "false")) {
-                                       base->sync &= ~FB_SYNC_EXT;
-                               } else {
-                                       base->sync |= FB_SYNC_EXT;
-                               }
+                                       &base->pixclock,
+                                       &base->left_margin, &base->right_margin,
+                                       &base->upper_margin, &base->lower_margin,
+                                       &base->hsync_len, &base->vsync_len);
+                       } else {
+                               int base_pixclock;
+                               int base_left_margin, base_right_margin;
+                               int base_upper_margin, base_lower_margin;
+                               int base_hsync_len, base_vsync_len;
+                               sscanf(p, "%d %d %d %d %d %d %d",
+                                       &base_pixclock,
+                                       &base_left_margin, &base_right_margin,
+                                       &base_upper_margin, &base_lower_margin,
+                                       &base_hsync_len, &base_vsync_len);
+                               base->pixclock = base_pixclock;
+                               base->left_margin = base_left_margin;
+                               base->right_margin = base_right_margin;
+                               base->upper_margin = base_upper_margin;
+                               base->lower_margin = base_lower_margin;
+                               base->hsync_len = base_hsync_len;
+                               base->vsync_len = base_vsync_len;
                        }
+//bb_error_msg("TIM[%s]", p);
+                       break;
+               case 2:
+               case 3: {
+                       static const uint32_t syncs[] = {FB_VMODE_INTERLACED, FB_VMODE_DOUBLE};
+                       ss(&base->vmode, syncs[i-2], p, "false");
+//bb_error_msg("VMODE[%s]", p);
+                       break;
+               }
+               case 4:
+               case 5:
+               case 6: {
+                       static const uint32_t syncs[] = {FB_SYNC_VERT_HIGH_ACT, FB_SYNC_HOR_HIGH_ACT, FB_SYNC_COMP_HIGH_ACT};
+                       ss(&base->sync, syncs[i-4], p, "low");
+//bb_error_msg("SYNC[%s]", p);
+                       break;
+               }
+               case 7:
+                       ss(&base->sync, FB_SYNC_EXT, p, "false");
+//bb_error_msg("EXTSYNC[%s]", p);
+                       break;
+               case 8: {
+                       int red_offset, red_length;
+                       int green_offset, green_length;
+                       int blue_offset, blue_length;
+                       int transp_offset, transp_length;
 
-                       if (strstr(buf, "endmode"))
-                               return 1;
+                       sscanf(p, "%d/%d,%d/%d,%d/%d,%d/%d",
+                               &red_length, &red_offset,
+                               &green_length, &green_offset,
+                               &blue_length, &blue_offset,
+                               &transp_length, &transp_offset);
+                       base->red.offset = red_offset;
+                       base->red.length = red_length;
+                       base->red.msb_right = 0;
+                       base->green.offset = green_offset;
+                       base->green.length = green_length;
+                       base->green.msb_right = 0;
+                       base->blue.offset = blue_offset;
+                       base->blue.length = blue_length;
+                       base->blue.msb_right = 0;
+                       base->transp.offset = transp_offset;
+                       base->transp.length = transp_length;
+                       base->transp.msb_right = 0;
+               }
                }
        }
-#else
-       bb_error_msg("mode reading not compiled in");
-#endif
        return 0;
 }
+#endif
 
-static inline void setmode(struct fb_var_screeninfo *base,
-                                       struct fb_var_screeninfo *set)
-{
-       if ((int) set->xres > 0)
-               base->xres = set->xres;
-       if ((int) set->yres > 0)
-               base->yres = set->yres;
-       if ((int) set->xres_virtual > 0)
-               base->xres_virtual = set->xres_virtual;
-       if ((int) set->yres_virtual > 0)
-               base->yres_virtual = set->yres_virtual;
-       if ((int) set->bits_per_pixel > 0)
-               base->bits_per_pixel = set->bits_per_pixel;
-}
-
-static inline void showmode(struct fb_var_screeninfo *v)
+static NOINLINE void showmode(struct fb_var_screeninfo *v)
 {
        double drate = 0, hrate = 0, vrate = 0;
 
@@ -286,7 +415,7 @@ static inline void showmode(struct fb_var_screeninfo *v)
                vrate = hrate / (v->upper_margin + v->yres + v->lower_margin + v->vsync_len);
        }
        printf("\nmode \"%ux%u-%u\"\n"
-#ifdef CONFIG_FEATURE_FBSET_FANCY
+#if ENABLE_FEATURE_FBSET_FANCY
        "\t# D: %.3f MHz, H: %.3f kHz, V: %.3f Hz\n"
 #endif
        "\tgeometry %u %u %u %u %u\n"
@@ -295,7 +424,7 @@ static inline void showmode(struct fb_var_screeninfo *v)
        "\trgba %u/%u,%u/%u,%u/%u,%u/%u\n"
        "endmode\n\n",
                v->xres, v->yres, (int) (vrate + 0.5),
-#ifdef CONFIG_FEATURE_FBSET_FANCY
+#if ENABLE_FEATURE_FBSET_FANCY
                drate / 1e6, hrate / 1e3, vrate,
 #endif
                v->xres, v->yres, v->xres_virtual, v->yres_virtual, v->bits_per_pixel,
@@ -306,29 +435,41 @@ static inline void showmode(struct fb_var_screeninfo *v)
                        v->blue.length, v->blue.offset, v->transp.length, v->transp.offset);
 }
 
-#ifdef STANDALONE
-int main(int argc, char **argv)
-#else
-int fbset_main(int argc, char **argv);
+int fbset_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
 int fbset_main(int argc, char **argv)
-#endif
 {
-       struct fb_var_screeninfo var, varset;
+       enum {
+               OPT_CHANGE   = (1 << 0),
+               OPT_SHOW     = (1 << 1),
+               OPT_READMODE = (1 << 2),
+               OPT_ALL      = (1 << 3),
+       };
+       struct fb_var_screeninfo var_old, var_set;
        int fh, i;
+       unsigned options = 0;
+
        const char *fbdev = DEFAULTFBDEV;
-       const char *modefile = DEFAULTFBMODE;
-       char *thisarg, *mode = NULL;
+       IF_FEATURE_FBSET_READMODE(const char *modefile = DEFAULTFBMODE;)
+       char *thisarg;
+       char *mode = mode; /* for compiler */
 
-       memset(&varset, 0xFF, sizeof(varset));
+       memset(&var_set, 0xff, sizeof(var_set)); /* set all to -1 */
 
        /* parse cmd args.... why do they have to make things so difficult? */
        argv++;
        argc--;
-       for (; argc > 0 && (thisarg = *argv); argc--, argv++) {
-               for (i = 0; g_cmdoptions[i].name[0]; i++) {
-                       if (strcmp(thisarg, g_cmdoptions[i].name))
+       for (; argc > 0 && (thisarg = *argv) != NULL; argc--, argv++) {
+               if (thisarg[0] != '-') {
+                       if (!ENABLE_FEATURE_FBSET_READMODE || argc != 1)
+                               bb_show_usage();
+                       mode = thisarg;
+                       options |= OPT_READMODE;
+                       goto contin;
+               }
+               for (i = 0; i < ARRAY_SIZE(g_cmdoptions); i++) {
+                       if (strcmp(thisarg + 1, g_cmdoptions[i].name) != 0)
                                continue;
-                       if (argc-1 < g_cmdoptions[i].param_count)
+                       if (argc <= g_cmdoptions[i].param_count)
                                bb_show_usage();
 
                        switch (g_cmdoptions[i].code) {
@@ -336,71 +477,92 @@ int fbset_main(int argc, char **argv)
                                fbdev = argv[1];
                                break;
                        case CMD_DB:
-                               modefile = argv[1];
+                               IF_FEATURE_FBSET_READMODE(modefile = argv[1];)
+                               break;
+                       case CMD_ALL:
+                               options |= OPT_ALL;
+                               break;
+                       case CMD_SHOW:
+                               options |= OPT_SHOW;
                                break;
                        case CMD_GEOMETRY:
-                               varset.xres = xatou32(argv[1]);
-                               varset.yres = xatou32(argv[2]);
-                               varset.xres_virtual = xatou32(argv[3]);
-                               varset.yres_virtual = xatou32(argv[4]);
-                               varset.bits_per_pixel = xatou32(argv[5]);
+                               var_set.xres = xatou32(argv[1]);
+                               var_set.yres = xatou32(argv[2]);
+                               var_set.xres_virtual = xatou32(argv[3]);
+                               var_set.yres_virtual = xatou32(argv[4]);
+                               var_set.bits_per_pixel = xatou32(argv[5]);
                                break;
                        case CMD_TIMING:
-                               varset.pixclock = xatou32(argv[1]);
-                               varset.left_margin = xatou32(argv[2]);
-                               varset.right_margin = xatou32(argv[3]);
-                               varset.upper_margin = xatou32(argv[4]);
-                               varset.lower_margin = xatou32(argv[5]);
-                               varset.hsync_len = xatou32(argv[6]);
-                               varset.vsync_len = xatou32(argv[7]);
+                               var_set.pixclock = xatou32(argv[1]);
+                               var_set.left_margin = xatou32(argv[2]);
+                               var_set.right_margin = xatou32(argv[3]);
+                               var_set.upper_margin = xatou32(argv[4]);
+                               var_set.lower_margin = xatou32(argv[5]);
+                               var_set.hsync_len = xatou32(argv[6]);
+                               var_set.vsync_len = xatou32(argv[7]);
                                break;
-                       case CMD_ALL:
-                               g_options |= OPT_ALL;
+                       case CMD_ACCEL:
                                break;
-                       case CMD_CHANGE:
-                               g_options |= OPT_CHANGE;
+                       case CMD_HSYNC:
+                               var_set.sync |= FB_SYNC_HOR_HIGH_ACT;
                                break;
-#ifdef CONFIG_FEATURE_FBSET_FANCY
+                       case CMD_VSYNC:
+                               var_set.sync |= FB_SYNC_VERT_HIGH_ACT;
+                               break;
+#if ENABLE_FEATURE_FBSET_FANCY
                        case CMD_XRES:
-                               varset.xres = xatou32(argv[1]);
+                               var_set.xres = xatou32(argv[1]);
                                break;
                        case CMD_YRES:
-                               varset.yres = xatou32(argv[1]);
+                               var_set.yres = xatou32(argv[1]);
                                break;
                        case CMD_DEPTH:
-                               varset.bits_per_pixel = xatou32(argv[1]);
+                               var_set.bits_per_pixel = xatou32(argv[1]);
                                break;
 #endif
                        }
+                       switch (g_cmdoptions[i].code) {
+                       case CMD_FB:
+                       case CMD_DB:
+                       case CMD_ALL:
+                       case CMD_SHOW:
+                               break;
+                       default:
+                               /* other commands imply changes */
+                               options |= OPT_CHANGE;
+                       }
                        argc -= g_cmdoptions[i].param_count;
                        argv += g_cmdoptions[i].param_count;
-                       break;
-               }
-               if (!g_cmdoptions[i].name[0]) {
-                       if (argc != 1)
-                               bb_show_usage();
-                       mode = *argv;
-                       g_options |= OPT_READMODE;
+                       goto contin;
                }
+               bb_show_usage();
+ contin: ;
        }
 
        fh = xopen(fbdev, O_RDONLY);
-       xioctl(fh, FBIOGET_VSCREENINFO, &var);
-       if (g_options & OPT_READMODE) {
-               if (!readmode(&var, modefile, mode)) {
+       xioctl(fh, FBIOGET_VSCREENINFO, &var_old);
+
+       if (options & OPT_READMODE) {
+#if ENABLE_FEATURE_FBSET_READMODE
+               if (!read_mode_db(&var_old, modefile, mode)) {
                        bb_error_msg_and_die("unknown video mode '%s'", mode);
                }
+               options |= OPT_CHANGE;
+#endif
        }
 
-       setmode(&var, &varset);
-       if (g_options & OPT_CHANGE) {
-               if (g_options & OPT_ALL)
-                       var.activate = FB_ACTIVATE_ALL;
-               xioctl(fh, FBIOPUT_VSCREENINFO, &var);
+       if (options & OPT_CHANGE) {
+               copy_changed_values(&var_old, &var_set);
+               if (options & OPT_ALL)
+                       var_old.activate = FB_ACTIVATE_ALL;
+               xioctl(fh, FBIOPUT_VSCREENINFO, &var_old);
        }
-       showmode(&var);
-       /* Don't close the file, as exiting will take care of that */
-       /* close(fh); */
+
+       if (options == 0 || (options & OPT_SHOW))
+               showmode(&var_old);
+
+       if (ENABLE_FEATURE_CLEAN_UP)
+               close(fh);
 
        return EXIT_SUCCESS;
 }