FFmpeg/libavfilter/parseutils.c

/*
 * copyright (c) 2009 Stefano Sabatini
 * This file is part of FFmpeg.
 *
 * FFmpeg is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * FFmpeg 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with FFmpeg; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */

/**
 * @file
 * parsing utils
 */

#include <strings.h>
#include "libavutil/avutil.h"
#include "libavutil/avstring.h"
#include "libavutil/random_seed.h"
#include "parseutils.h"

#define WHITESPACES " \n\t"

char *av_get_token(const char **buf, const char *term)
{
    char *out = av_malloc(strlen(*buf) + 1);
    char *ret= out, *end= out;
    const char *p = *buf;
    if (!out) return NULL;
    p += strspn(p, WHITESPACES);

    while(*p && !strspn(p, term)) {
        char c = *p++;
        if(c == '\\' && *p){
            *out++ = *p++;
            end= out;
        }else if(c == '\''){
            while(*p && *p != '\'')
                *out++ = *p++;
            if(*p){
                p++;
                end= out;
            }
        }else{
            *out++ = c;
        }
    }

    do{
        *out-- = 0;
    }while(out >= end && strspn(out, WHITESPACES));

    *buf = p;

    return ret;
}

typedef struct {
    const char *name;            ///< a string representing the name of the color
    uint8_t     rgb_color[3];    ///< RGB values for the color
} ColorEntry;

static ColorEntry color_table[] = {
    { "AliceBlue",            { 0xF0, 0xF8, 0xFF } },
    { "AntiqueWhite",         { 0xFA, 0xEB, 0xD7 } },
    { "Aqua",                 { 0x00, 0xFF, 0xFF } },
    { "Aquamarine",           { 0x7F, 0xFF, 0xD4 } },
    { "Azure",                { 0xF0, 0xFF, 0xFF } },
    { "Beige",                { 0xF5, 0xF5, 0xDC } },
    { "Bisque",               { 0xFF, 0xE4, 0xC4 } },
    { "Black",                { 0x00, 0x00, 0x00 } },
    { "BlanchedAlmond",       { 0xFF, 0xEB, 0xCD } },
    { "Blue",                 { 0x00, 0x00, 0xFF } },
    { "BlueViolet",           { 0x8A, 0x2B, 0xE2 } },
    { "Brown",                { 0xA5, 0x2A, 0x2A } },
    { "BurlyWood",            { 0xDE, 0xB8, 0x87 } },
    { "CadetBlue",            { 0x5F, 0x9E, 0xA0 } },
    { "Chartreuse",           { 0x7F, 0xFF, 0x00 } },
    { "Chocolate",            { 0xD2, 0x69, 0x1E } },
    { "Coral",                { 0xFF, 0x7F, 0x50 } },
    { "CornflowerBlue",       { 0x64, 0x95, 0xED } },
    { "Cornsilk",             { 0xFF, 0xF8, 0xDC } },
    { "Crimson",              { 0xDC, 0x14, 0x3C } },
    { "Cyan",                 { 0x00, 0xFF, 0xFF } },
    { "DarkBlue",             { 0x00, 0x00, 0x8B } },
    { "DarkCyan",             { 0x00, 0x8B, 0x8B } },
    { "DarkGoldenRod",        { 0xB8, 0x86, 0x0B } },
    { "DarkGray",             { 0xA9, 0xA9, 0xA9 } },
    { "DarkGreen",            { 0x00, 0x64, 0x00 } },
    { "DarkKhaki",            { 0xBD, 0xB7, 0x6B } },
    { "DarkMagenta",          { 0x8B, 0x00, 0x8B } },
    { "DarkOliveGreen",       { 0x55, 0x6B, 0x2F } },
    { "Darkorange",           { 0xFF, 0x8C, 0x00 } },
    { "DarkOrchid",           { 0x99, 0x32, 0xCC } },
    { "DarkRed",              { 0x8B, 0x00, 0x00 } },
    { "DarkSalmon",           { 0xE9, 0x96, 0x7A } },
    { "DarkSeaGreen",         { 0x8F, 0xBC, 0x8F } },
    { "DarkSlateBlue",        { 0x48, 0x3D, 0x8B } },
    { "DarkSlateGray",        { 0x2F, 0x4F, 0x4F } },
    { "DarkTurquoise",        { 0x00, 0xCE, 0xD1 } },
    { "DarkViolet",           { 0x94, 0x00, 0xD3 } },
    { "DeepPink",             { 0xFF, 0x14, 0x93 } },
    { "DeepSkyBlue",          { 0x00, 0xBF, 0xFF } },
    { "DimGray",              { 0x69, 0x69, 0x69 } },
    { "DodgerBlue",           { 0x1E, 0x90, 0xFF } },
    { "FireBrick",            { 0xB2, 0x22, 0x22 } },
    { "FloralWhite",          { 0xFF, 0xFA, 0xF0 } },
    { "ForestGreen",          { 0x22, 0x8B, 0x22 } },
    { "Fuchsia",              { 0xFF, 0x00, 0xFF } },
    { "Gainsboro",            { 0xDC, 0xDC, 0xDC } },
    { "GhostWhite",           { 0xF8, 0xF8, 0xFF } },
    { "Gold",                 { 0xFF, 0xD7, 0x00 } },
    { "GoldenRod",            { 0xDA, 0xA5, 0x20 } },
    { "Gray",                 { 0x80, 0x80, 0x80 } },
    { "Green",                { 0x00, 0x80, 0x00 } },
    { "GreenYellow",          { 0xAD, 0xFF, 0x2F } },
    { "HoneyDew",             { 0xF0, 0xFF, 0xF0 } },
    { "HotPink",              { 0xFF, 0x69, 0xB4 } },
    { "IndianRed",            { 0xCD, 0x5C, 0x5C } },
    { "Indigo",               { 0x4B, 0x00, 0x82 } },
    { "Ivory",                { 0xFF, 0xFF, 0xF0 } },
    { "Khaki",                { 0xF0, 0xE6, 0x8C } },
    { "Lavender",             { 0xE6, 0xE6, 0xFA } },
    { "LavenderBlush",        { 0xFF, 0xF0, 0xF5 } },
    { "LawnGreen",            { 0x7C, 0xFC, 0x00 } },
    { "LemonChiffon",         { 0xFF, 0xFA, 0xCD } },
    { "LightBlue",            { 0xAD, 0xD8, 0xE6 } },
    { "LightCoral",           { 0xF0, 0x80, 0x80 } },
    { "LightCyan",            { 0xE0, 0xFF, 0xFF } },
    { "LightGoldenRodYellow", { 0xFA, 0xFA, 0xD2 } },
    { "LightGrey",            { 0xD3, 0xD3, 0xD3 } },
    { "LightGreen",           { 0x90, 0xEE, 0x90 } },
    { "LightPink",            { 0xFF, 0xB6, 0xC1 } },
    { "LightSalmon",          { 0xFF, 0xA0, 0x7A } },
    { "LightSeaGreen",        { 0x20, 0xB2, 0xAA } },
    { "LightSkyBlue",         { 0x87, 0xCE, 0xFA } },
    { "LightSlateGray",       { 0x77, 0x88, 0x99 } },
    { "LightSteelBlue",       { 0xB0, 0xC4, 0xDE } },
    { "LightYellow",          { 0xFF, 0xFF, 0xE0 } },
    { "Lime",                 { 0x00, 0xFF, 0x00 } },
    { "LimeGreen",            { 0x32, 0xCD, 0x32 } },
    { "Linen",                { 0xFA, 0xF0, 0xE6 } },
    { "Magenta",              { 0xFF, 0x00, 0xFF } },
    { "Maroon",               { 0x80, 0x00, 0x00 } },
    { "MediumAquaMarine",     { 0x66, 0xCD, 0xAA } },
    { "MediumBlue",           { 0x00, 0x00, 0xCD } },
    { "MediumOrchid",         { 0xBA, 0x55, 0xD3 } },
    { "MediumPurple",         { 0x93, 0x70, 0xD8 } },
    { "MediumSeaGreen",       { 0x3C, 0xB3, 0x71 } },
    { "MediumSlateBlue",      { 0x7B, 0x68, 0xEE } },
    { "MediumSpringGreen",    { 0x00, 0xFA, 0x9A } },
    { "MediumTurquoise",      { 0x48, 0xD1, 0xCC } },
    { "MediumVioletRed",      { 0xC7, 0x15, 0x85 } },
    { "MidnightBlue",         { 0x19, 0x19, 0x70 } },
    { "MintCream",            { 0xF5, 0xFF, 0xFA } },
    { "MistyRose",            { 0xFF, 0xE4, 0xE1 } },
    { "Moccasin",             { 0xFF, 0xE4, 0xB5 } },
    { "NavajoWhite",          { 0xFF, 0xDE, 0xAD } },
    { "Navy",                 { 0x00, 0x00, 0x80 } },
    { "OldLace",              { 0xFD, 0xF5, 0xE6 } },
    { "Olive",                { 0x80, 0x80, 0x00 } },
    { "OliveDrab",            { 0x6B, 0x8E, 0x23 } },
    { "Orange",               { 0xFF, 0xA5, 0x00 } },
    { "OrangeRed",            { 0xFF, 0x45, 0x00 } },
    { "Orchid",               { 0xDA, 0x70, 0xD6 } },
    { "PaleGoldenRod",        { 0xEE, 0xE8, 0xAA } },
    { "PaleGreen",            { 0x98, 0xFB, 0x98 } },
    { "PaleTurquoise",        { 0xAF, 0xEE, 0xEE } },
    { "PaleVioletRed",        { 0xD8, 0x70, 0x93 } },
    { "PapayaWhip",           { 0xFF, 0xEF, 0xD5 } },
    { "PeachPuff",            { 0xFF, 0xDA, 0xB9 } },
    { "Peru",                 { 0xCD, 0x85, 0x3F } },
    { "Pink",                 { 0xFF, 0xC0, 0xCB } },
    { "Plum",                 { 0xDD, 0xA0, 0xDD } },
    { "PowderBlue",           { 0xB0, 0xE0, 0xE6 } },
    { "Purple",               { 0x80, 0x00, 0x80 } },
    { "Red",                  { 0xFF, 0x00, 0x00 } },
    { "RosyBrown",            { 0xBC, 0x8F, 0x8F } },
    { "RoyalBlue",            { 0x41, 0x69, 0xE1 } },
    { "SaddleBrown",          { 0x8B, 0x45, 0x13 } },
    { "Salmon",               { 0xFA, 0x80, 0x72 } },
    { "SandyBrown",           { 0xF4, 0xA4, 0x60 } },
    { "SeaGreen",             { 0x2E, 0x8B, 0x57 } },
    { "SeaShell",             { 0xFF, 0xF5, 0xEE } },
    { "Sienna",               { 0xA0, 0x52, 0x2D } },
    { "Silver",               { 0xC0, 0xC0, 0xC0 } },
    { "SkyBlue",              { 0x87, 0xCE, 0xEB } },
    { "SlateBlue",            { 0x6A, 0x5A, 0xCD } },
    { "SlateGray",            { 0x70, 0x80, 0x90 } },
    { "Snow",                 { 0xFF, 0xFA, 0xFA } },
    { "SpringGreen",          { 0x00, 0xFF, 0x7F } },
    { "SteelBlue",            { 0x46, 0x82, 0xB4 } },
    { "Tan",                  { 0xD2, 0xB4, 0x8C } },
    { "Teal",                 { 0x00, 0x80, 0x80 } },
    { "Thistle",              { 0xD8, 0xBF, 0xD8 } },
    { "Tomato",               { 0xFF, 0x63, 0x47 } },
    { "Turquoise",            { 0x40, 0xE0, 0xD0 } },
    { "Violet",               { 0xEE, 0x82, 0xEE } },
    { "Wheat",                { 0xF5, 0xDE, 0xB3 } },
    { "White",                { 0xFF, 0xFF, 0xFF } },
    { "WhiteSmoke",           { 0xF5, 0xF5, 0xF5 } },
    { "Yellow",               { 0xFF, 0xFF, 0x00 } },
    { "YellowGreen",          { 0x9A, 0xCD, 0x32 } },
};

static int color_table_compare(const void *lhs, const void *rhs)
{
    return strcasecmp(lhs, ((const ColorEntry *)rhs)->name);
}

#define ALPHA_SEP '@'

int av_parse_color(uint8_t *rgba_color, const char *color_string, void *log_ctx)
{
    char *tail, color_string2[128];
    const ColorEntry *entry;
    av_strlcpy(color_string2, color_string, sizeof(color_string2));
    if ((tail = strchr(color_string2, ALPHA_SEP)))
        *tail++ = 0;
    rgba_color[3] = 255;

    if (!strcasecmp(color_string2, "random") || !strcasecmp(color_string2, "bikeshed")) {
        int rgba = av_get_random_seed();
        rgba_color[0] = rgba >> 24;
        rgba_color[1] = rgba >> 16;
        rgba_color[2] = rgba >> 8;
        rgba_color[3] = rgba;
    } else if (!strncmp(color_string2, "0x", 2)) {
        char *tail;
        int len = strlen(color_string2);
        unsigned int rgba = strtoul(color_string2, &tail, 16);

        if (*tail || (len != 8 && len != 10)) {
            av_log(log_ctx, AV_LOG_ERROR, "Invalid 0xRRGGBB[AA] color string: '%s'\n", color_string2);
            return AVERROR(EINVAL);
        }
        if (len == 10) {
            rgba_color[3] = rgba;
            rgba >>= 8;
        }
        rgba_color[0] = rgba >> 16;
        rgba_color[1] = rgba >> 8;
        rgba_color[2] = rgba;
    } else {
        entry = bsearch(color_string2,
                        color_table,
                        FF_ARRAY_ELEMS(color_table),
                        sizeof(ColorEntry),
                        color_table_compare);
        if (!entry) {
            av_log(log_ctx, AV_LOG_ERROR, "Cannot find color '%s'\n", color_string2);
            return AVERROR(EINVAL);
        }
        memcpy(rgba_color, entry->rgb_color, 3);
    }

    if (tail) {
        unsigned long int alpha;
        const char *alpha_string = tail;
        if (!strncmp(alpha_string, "0x", 2)) {
            alpha = strtoul(alpha_string, &tail, 16);
        } else {
            alpha = strtoul(alpha_string, &tail, 10);
            if (*tail) {
                double d = strtod(alpha_string, &tail);
                alpha = d * 255;
            }
        }

        if (tail == alpha_string || *tail || alpha > 255) {
            av_log(log_ctx, AV_LOG_ERROR, "Invalid alpha value specifier '%s' in '%s'\n",
                   alpha_string, color_string);
            return AVERROR(EINVAL);
        }
        rgba_color[3] = alpha;
    }

    return 0;
}

/**
 * Store the value in the field in ctx that is named like key.
 * ctx must be an AVClass context, storing is done using AVOptions.
 *
 * @param buf the string to parse, buf will be updated to point at the
 * separator just after the parsed key/value pair
 * @param key_val_sep a 0-terminated list of characters used to
 * separate key from value
 * @param pairs_sep a 0-terminated list of characters used to separate
 * two pairs from each other
 * @return 0 if the key/value pair has been successfully parsed and
 * set, or a negative value corresponding to an AVERROR code in case
 * of error:
 * AVERROR(EINVAL) if the key/value pair cannot be parsed,
 * the error code issued by av_set_string3() if the key/value pair
 * cannot be set
 */
static int parse_key_value_pair(void *ctx, const char **buf,
                                const char *key_val_sep, const char *pairs_sep)
{
    char *key = av_get_token(buf, key_val_sep);
    char *val;
    int ret;

    if (*key && strspn(*buf, key_val_sep)) {
        (*buf)++;
        val = av_get_token(buf, pairs_sep);
    } else {
        av_log(ctx, AV_LOG_ERROR, "Missing key or no key/value separator found after key '%s'\n", key);
        av_free(key);
        return AVERROR(EINVAL);
    }

    av_log(ctx, AV_LOG_DEBUG, "Setting value '%s' for key '%s'\n", val, key);

    ret = av_set_string3(ctx, key, val, 1, NULL);
    if (ret == AVERROR(ENOENT))
        av_log(ctx, AV_LOG_ERROR, "Key '%s' not found.\n", key);

    av_free(key);
    av_free(val);
    return ret;
}

int av_set_options_string(void *ctx, const char *opts,
                          const char *key_val_sep, const char *pairs_sep)
{
    int ret, count = 0;

    while (*opts) {
        if ((ret = parse_key_value_pair(ctx, &opts, key_val_sep, pairs_sep)) < 0)
            return ret;
        count++;

        if (*opts)
            opts++;
    }

    return count;
}

#ifdef TEST

#undef printf

typedef struct TestContext
{
    const AVClass *class;
    int num;
    int toggle;
    char *string;
    int flags;
    AVRational rational;
} TestContext;

#define OFFSET(x) offsetof(TestContext, x)

#define TEST_FLAG_COOL 01
#define TEST_FLAG_LAME 02
#define TEST_FLAG_MU   04

static const AVOption test_options[]= {
{"num",      "set num",        OFFSET(num),      FF_OPT_TYPE_INT,      0,              0,        100                 },
{"toggle",   "set toggle",     OFFSET(toggle),   FF_OPT_TYPE_INT,      0,              0,        1                   },
{"rational", "set rational",   OFFSET(rational), FF_OPT_TYPE_RATIONAL, 0,              0,        10                  },
{"string",   "set string",     OFFSET(string),   FF_OPT_TYPE_STRING,   0,              CHAR_MIN, CHAR_MAX            },
{"flags",    "set flags",      OFFSET(flags),    FF_OPT_TYPE_FLAGS,    0,              0,        INT_MAX, 0, "flags" },
{"cool",     "set cool flag ", 0,                FF_OPT_TYPE_CONST,    TEST_FLAG_COOL, INT_MIN,  INT_MAX, 0, "flags" },
{"lame",     "set lame flag ", 0,                FF_OPT_TYPE_CONST,    TEST_FLAG_LAME, INT_MIN,  INT_MAX, 0, "flags" },
{"mu",       "set mu flag ",   0,                FF_OPT_TYPE_CONST,    TEST_FLAG_MU,   INT_MIN,  INT_MAX, 0, "flags" },
{NULL},
};

static const char *test_get_name(void *ctx)
{
    return "test";
}

static const AVClass test_class = {
    "TestContext",
    test_get_name,
    test_options
};

int main(void)
{
    int i;

    const char *strings[] = {
        "''",
        "",
        ":",
        "\\",
        "'",
        "    ''    :",
        "    ''  ''  :",
        "foo   '' :",
        "'foo'",
        "foo     ",
        "foo\\",
        "foo':  blah:blah",
        "foo\\:  blah:blah",
        "foo\'",
        "'foo :  '  :blahblah",
        "\\ :blah",
        "     foo",
        "      foo       ",
        "      foo     \\ ",
        "foo ':blah",
        " foo   bar    :   blahblah",
        "\\f\\o\\o",
        "'foo : \\ \\  '   : blahblah",
        "'\\fo\\o:': blahblah",
        "\\'fo\\o\\:':  foo  '  :blahblah"
    };

    for (i=0; i < FF_ARRAY_ELEMS(strings); i++) {
        const char *p= strings[i];
        printf("|%s|", p);
        printf(" -> |%s|", av_get_token(&p, ":"));
        printf(" + |%s|\n", p);
    }

    printf("\nTesting av_parse_color()\n");
    {
        uint8_t rgba[4];
        const char *color_names[] = {
            "bikeshed",
            "RaNdOm",
            "foo",
            "red",
            "Red ",
            "RED",
            "Violet",
            "Yellow",
            "Red",
            "0x000000",
            "0x0000000",
            "0xff000000",
            "0x3e34ff",
            "0x3e34ffaa",
            "0xffXXee",
            "0xfoobar",
            "0xffffeeeeeeee",
            "red@foo",
            "random@10",
            "0xff0000@1.0",
            "red@",
            "red@0xfff",
            "red@0xf",
            "red@2",
            "red@0.1",
            "red@-1",
            "red@0.5",
            "red@1.0",
            "red@256",
            "red@10foo",
            "red@-1.0",
            "red@-0.0",
        };

        av_log_set_level(AV_LOG_DEBUG);

        for (int i = 0;  i < FF_ARRAY_ELEMS(color_names); i++) {
            if (av_parse_color(rgba, color_names[i], NULL) >= 0)
                printf("%s -> R(%d) G(%d) B(%d) A(%d)\n", color_names[i], rgba[0], rgba[1], rgba[2], rgba[3]);
        }
    }

    printf("\nTesting av_set_options_string()\n");
    {
        TestContext test_ctx;
        const char *options[] = {
            "",
            ":",
            "=",
            "foo=:",
            ":=foo",
            "=foo",
            "foo=",
            "foo",
            "foo=val",
            "foo==val",
            "toggle=:",
            "string=:",
            "toggle=1 : foo",
            "toggle=100",
            "toggle==1",
            "flags=+mu-lame : num=42: toggle=0",
            "num=42 : string=blahblah",
            "rational=0 : rational=1/2 : rational=1/-1",
            "rational=-1/0",
        };

        test_ctx.class = &test_class;
        av_opt_set_defaults2(&test_ctx, 0, 0);
        test_ctx.string = av_strdup("default");

        av_log_set_level(AV_LOG_DEBUG);

        for (i=0; i < FF_ARRAY_ELEMS(options); i++) {
            av_log(&test_ctx, AV_LOG_DEBUG, "Setting options string '%s'\n", options[i]);
            if (av_set_options_string(&test_ctx, options[i], "=", ":") < 0)
                av_log(&test_ctx, AV_LOG_ERROR, "Error setting options string: '%s'\n", options[i]);
            printf("\n");
        }
    }

    return 0;
}

#endif