Add hb_feature_to/from_string()
diff --git a/src/hb-common.cc b/src/hb-common.cc index 1301ab2..33a514d 100644 --- a/src/hb-common.cc +++ b/src/hb-common.cc
@@ -58,6 +58,15 @@ return HB_TAG_CHAR4 (tag); } +void +hb_tag_to_string (hb_tag_t tag, char *buf) +{ + buf[0] = (char) (uint8_t) (tag >> 24); + buf[1] = (char) (uint8_t) (tag >> 16); + buf[2] = (char) (uint8_t) (tag >> 8); + buf[3] = (char) (uint8_t) (tag >> 0); +} + /* hb_direction_t */
diff --git a/src/hb-common.h b/src/hb-common.h index 920bd32..cc221d3 100644 --- a/src/hb-common.h +++ b/src/hb-common.h
@@ -95,10 +95,14 @@ #define HB_TAG_NONE HB_TAG(0,0,0,0) -/* len=-1 means str is NUL-terminated */ +/* len=-1 means str is NUL-terminated. */ hb_tag_t hb_tag_from_string (const char *str, int len); +/* buf should have 4 bytes. */ +void +hb_tag_to_string (hb_tag_t tag, char *buf); + /* hb_direction_t */
diff --git a/src/hb-shape.cc b/src/hb-shape.cc index 5aa587b..6619c19 100644 --- a/src/hb-shape.cc +++ b/src/hb-shape.cc
@@ -1,5 +1,6 @@ /* * Copyright © 2009 Red Hat, Inc. + * Copyright © 2012 Google, Inc. * * This is part of HarfBuzz, a text shaping library. * @@ -22,6 +23,7 @@ * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS. * * Red Hat Author(s): Behdad Esfahbod + * Google Author(s): Behdad Esfahbod */ #include "hb-private.hh" @@ -32,6 +34,172 @@ #include "hb-font-private.hh" +static void +parse_space (const char **pp, const char *end) +{ + char c; +#define ISSPACE(c) ((c)==' '||(c)=='\f'||(c)=='\n'||(c)=='\r'||(c)=='\t'||(c)=='\v') + while (*pp < end && (c = **pp, ISSPACE (c))) + (*pp)++; +#undef ISSPACE +} + +static hb_bool_t +parse_char (const char **pp, const char *end, char c) +{ + parse_space (pp, end); + + if (*pp == end || **pp != c) + return false; + + (*pp)++; + return true; +} + +static hb_bool_t +parse_uint (const char **pp, const char *end, unsigned int *pv) +{ + char buf[32]; + strncpy (buf, *pp, end - *pp); + buf[ARRAY_LENGTH (buf) - 1] = '\0'; + + char *p = buf; + char *pend = p; + unsigned int v; + + v = strtol (p, &pend, 0); + + if (p == pend) + return false; + + *pv = v; + *pp += pend - p; + return true; +} + +static hb_bool_t +parse_feature_value_prefix (const char **pp, const char *end, hb_feature_t *feature) +{ + if (parse_char (pp, end, '-')) + feature->value = 0; + else { + parse_char (pp, end, '+'); + feature->value = 1; + } + + return true; +} + +static hb_bool_t +parse_feature_tag (const char **pp, const char *end, hb_feature_t *feature) +{ + const char *p = *pp; + char c; + + parse_space (pp, end); + +#define ISALNUM(c) (('a' <= (c) && (c) <= 'z') || ('A' <= (c) && (c) <= 'Z') || ('0' <= (c) && (c) <= '9')) + while (*pp < end && (c = **pp, ISALNUM(c))) + (*pp)++; +#undef ISALNUM + + if (p == *pp) + return false; + + feature->tag = hb_tag_from_string (p, *pp - p); + return true; +} + +static hb_bool_t +parse_feature_indices (const char **pp, const char *end, hb_feature_t *feature) +{ + parse_space (pp, end); + + hb_bool_t has_start; + + feature->start = 0; + feature->end = (unsigned int) -1; + + if (!parse_char (pp, end, '[')) + return true; + + has_start = parse_uint (pp, end, &feature->start); + + if (parse_char (pp, end, ':')) { + parse_uint (pp, end, &feature->end); + } else { + if (has_start) + feature->end = feature->start + 1; + } + + return parse_char (pp, end, ']'); +} + +static hb_bool_t +parse_feature_value_postfix (const char **pp, const char *end, hb_feature_t *feature) +{ + return !parse_char (pp, end, '=') || parse_uint (pp, end, &feature->value); +} + + +static hb_bool_t +parse_one_feature (const char **pp, const char *end, hb_feature_t *feature) +{ + return parse_feature_value_prefix (pp, end, feature) && + parse_feature_tag (pp, end, feature) && + parse_feature_indices (pp, end, feature) && + parse_feature_value_postfix (pp, end, feature) && + *pp == end; +} + +hb_bool_t +hb_feature_from_string (const char *str, int len, + hb_feature_t *feature) +{ + if (len < 0) + len = strlen (str); + + return parse_one_feature (&str, str + len, feature); +} + +void +hb_feature_to_string (hb_feature_t *feature, + char *buf, unsigned int size) +{ + if (unlikely (!size)) return; + + char s[128]; + unsigned int len = 0; + if (feature->value == 0) + s[len++] = '-'; + hb_tag_to_string (feature->tag, s + len); + len += 4; + while (len && s[len - 1] == ' ') + len--; + if (feature->start != 0 || feature->start != (unsigned int) -1) + { + s[len++] = '['; + if (feature->start) + len += snprintf (s + len, ARRAY_LENGTH (s) - len, "%d", feature->start); + if (feature->end != feature->start + 1) { + s[len++] = ':'; + if (feature->end != (unsigned int) -1) + len += snprintf (s + len, ARRAY_LENGTH (s) - len, "%d", feature->end); + } + s[len++] = ']'; + } + if (feature->value > 1) + { + s[len++] = '='; + len += snprintf (s + len, ARRAY_LENGTH (s) - len, "%d", feature->value); + } + assert (len < ARRAY_LENGTH (s)); + len = MIN (len, size - 1); + memcpy (buf, s, len); + s[len] = '\0'; +} + + static const char **static_shaper_list; static
diff --git a/src/hb-shape.h b/src/hb-shape.h index 84bf3e7..90a188d 100644 --- a/src/hb-shape.h +++ b/src/hb-shape.h
@@ -1,5 +1,6 @@ /* * Copyright © 2009 Red Hat, Inc. + * Copyright © 2012 Google, Inc. * * This is part of HarfBuzz, a text shaping library. * @@ -22,6 +23,7 @@ * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS. * * Red Hat Author(s): Behdad Esfahbod + * Google Author(s): Behdad Esfahbod */ #ifndef HB_H_IN @@ -45,6 +47,17 @@ unsigned int end; } hb_feature_t; +/* len=-1 means str is NUL-terminated */ +hb_bool_t +hb_feature_from_string (const char *str, int len, + hb_feature_t *feature); + +/* something like 128 bytes is more than enough. + * nul-terminates. */ +void +hb_feature_to_string (hb_feature_t *feature, + char *buf, unsigned int size); + void hb_shape (hb_font_t *font,