fbset: fix mode matching code: original code may trigger false positive.

 E.g. fbset -n '16bit'
 succeeded at 'mode "640x480 16bit"' and that is wrong.
 Also parser is rewritten. By Vladimir.

function                                             old     new   delta
static.syncs                                           -      20     +20
g_options                                              4       -      -4
g_cmdoptions                                         432     385     -47
fbset_main                                          1842    1642    -200

1 files changed, 132 insertions, 117 deletions

diff --git a/util-linux/fbset.c b/util-linux/fbset.c
index 103ef6818..590918aab 100644
--- a/util-linux/fbset.c
+++ b/util-linux/fbset.c
@@ -18,11 +18,6 @@
 #define DEFAULTFBMODE "/etc/fb.modes"
 
 enum {
-        OPT_CHANGE   = (1 << 0),
-        OPT_INFO     = (1 << 1),
-        OPT_READMODE = (1 << 2),
-        OPT_ALL      = (1 << 9),
-
         CMD_FB = 1,
         CMD_DB = 2,
         CMD_GEOMETRY = 3,
@@ -61,8 +56,6 @@ enum {
 #endif
 };
 
-static unsigned g_options;
-
 /* Stuff stolen from the kernel's fb.h */
 #define FB_ACTIVATE_ALL 64
 enum {
@@ -114,66 +107,66 @@ struct fb_var_screeninfo {
 
 
 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 },
+        /*"12345678" + NUL */
+        { "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   },
 #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 },
+        { "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 }
 };
 
 #if ENABLE_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_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 */
 };
 #endif
 
 #if ENABLE_FEATURE_FBSET_READMODE
 static void ss(uint32_t *x, uint32_t flag, char *buf, const char *what)
 {
-        if (strstr(buf, what))
+        if (strcmp(buf, what) == 0)
                 *x &= ~flag;
         else
                 *x |= flag;
@@ -182,62 +175,77 @@ static void ss(uint32_t *x, uint32_t flag, char *buf, const char *what)
 static int readmode(struct fb_var_screeninfo *base, const char *fn,
                                         const char *mode)
 {
-        FILE *f;
-        char buf[256];
-        char *p = buf;
-
-        f = xfopen_for_read(fn);
-        while (fgets(buf, sizeof(buf), f)) {
-                p = strstr(buf, "mode ");
-                if (!p && !(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 = strstr(p + 5, mode);
+                p = strstr(token[1], mode);
                 if (!p)
                         continue;
-                p += strlen(mode);
-                if (!isspace(*p) && (*p != 0) && (*p != '"')
-                 && (*p != '\r') && (*p != '\n')
+                s = p + strlen(mode);
+                //bb_info_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! */
                 ) {
-                        continue;       /* almost, but not quite */
+                        //bb_info_msg("FOUND[%s][%s][%s][%d]", token[1], p, mode, isspace(*s));
+                        break;
                 }
+        }
 
-                while (fgets(buf, sizeof(buf), f)) {
-                        if ((p = strstr(buf, "geometry "))) {
-                                p += 9;
-                                /* FIXME: catastrophic on arches with 64bit ints */
-                                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;
-                                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;
-                                ss(&base->vmode, FB_VMODE_INTERLACED, buf, "false");
-                        } else if ((p = strstr(buf, "double "))) {
-                                //p += 7;
-                                ss(&base->vmode, FB_VMODE_DOUBLE, buf, "false");
-                        } else if ((p = strstr(buf, "vsync "))) {
-                                //p += 6;
-                                ss(&base->sync, FB_SYNC_VERT_HIGH_ACT, buf, "low");
-                        } else if ((p = strstr(buf, "hsync "))) {
-                                //p += 6;
-                                ss(&base->sync, FB_SYNC_HOR_HIGH_ACT, buf, "low");
-                        } else if ((p = strstr(buf, "csync "))) {
-                                //p += 6;
-                                ss(&base->sync, FB_SYNC_COMP_HIGH_ACT, buf, "low");
-                        } else if ((p = strstr(buf, "extsync "))) {
-                                //p += 8;
-                                ss(&base->sync, FB_SYNC_EXT, buf, "false");
-                        }
+        if (!token[0])
+                return 0;
+
+        while (config_read(parser, token, 2, 1, "# \t", PARSE_NORMAL)) {
+                int i;
 
-                        if (strstr(buf, "endmode"))
-                                return 1;
+//bb_info_msg("???[%s][%s]", token[0], token[1]);
+                if (strcmp(token[0], "endmode") == 0) {
+//bb_info_msg("OK[%s]", mode);
+                        return 1;
+                }
+                p = token[1];
+                i = index_in_strings(
+                        "geometry\0timings\0interlaced\0double\0vsync\0hsync\0csync\0extsync\0",
+                        token[0]);
+                switch (i) {
+                case 0:
+                        /* FIXME: catastrophic on arches with 64bit ints */
+                        sscanf(p, "%d %d %d %d %d",
+                                &(base->xres), &(base->yres),
+                                &(base->xres_virtual), &(base->yres_virtual),
+                                &(base->bits_per_pixel));
+//bb_info_msg("GEO[%s]", p);
+                        break;
+                case 1:
+                        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));
+//bb_info_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_info_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_info_msg("SYNC[%s]", p);
+                        break;
+                }
+                case 7:
+                        ss(&base->sync, FB_SYNC_EXT, p, "false");
+//bb_info_msg("EXTSYNC[%s]", p);
+                        break;
                 }
         }
         return 0;
@@ -292,22 +300,30 @@ static void showmode(struct fb_var_screeninfo *v)
 int fbset_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
 int fbset_main(int argc, char **argv)
 {
+        enum {
+                OPT_CHANGE   = (1 << 0),
+                /*OPT_INFO     = (1 << 1), ??*/
+                OPT_READMODE = (1 << 2),
+                OPT_ALL      = (1 << 9),
+        };
         struct fb_var_screeninfo var, varset;
         int fh, i;
+        unsigned options = 0;
+
         const char *fbdev = DEFAULTFBDEV;
         const char *modefile = DEFAULTFBMODE;
         char *thisarg, *mode = NULL;
 
-        memset(&varset, 0xFF, sizeof(varset));
+        memset(&varset, 0xff, sizeof(varset));
 
         /* 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] == '-') 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) {
@@ -334,10 +350,10 @@ int fbset_main(int argc, char **argv)
                                 varset.vsync_len = xatou32(argv[7]);
                                 break;
                         case CMD_ALL:
-                                g_options |= OPT_ALL;
+                                options |= OPT_ALL;
                                 break;
                         case CMD_CHANGE:
-                                g_options |= OPT_CHANGE;
+                                options |= OPT_CHANGE;
                                 break;
 #if ENABLE_FEATURE_FBSET_FANCY
                         case CMD_XRES:
@@ -353,19 +369,18 @@ int fbset_main(int argc, char **argv)
                         }
                         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;
                 }
+                if (argc != 1)
+                        bb_show_usage();
+                mode = *argv;
+                options |= OPT_READMODE;
+ contin: ;
         }
 
         fh = xopen(fbdev, O_RDONLY);
         xioctl(fh, FBIOGET_VSCREENINFO, &var);
-        if (g_options & OPT_READMODE) {
+        if (options & OPT_READMODE) {
 #if !ENABLE_FEATURE_FBSET_READMODE
                 bb_show_usage();
 #else
@@ -376,8 +391,8 @@ int fbset_main(int argc, char **argv)
         }
 
         setmode(&var, &varset);
-        if (g_options & OPT_CHANGE) {
-                if (g_options & OPT_ALL)
+        if (options & OPT_CHANGE) {
+                if (options & OPT_ALL)
                         var.activate = FB_ACTIVATE_ALL;
                 xioctl(fh, FBIOPUT_VSCREENINFO, &var);
         }