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author | James Bursa <james@netsurf-browser.org> | 2002-04-22 09:24:35 +0000 |
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committer | James Bursa <james@netsurf-browser.org> | 2002-04-22 09:24:35 +0000 |
commit | 6d48b29c2bc7ce93eb6ac30f594bdcfb3aa97e11 (patch) | |
tree | 9d60d5b341264d7d7db555865b2583e0f6b7c19d /render/css.c | |
download | netsurf-6d48b29c2bc7ce93eb6ac30f594bdcfb3aa97e11.tar.gz netsurf-6d48b29c2bc7ce93eb6ac30f594bdcfb3aa97e11.tar.bz2 |
[project @ 2002-04-22 09:24:35 by bursa]
Initial revision
svn path=/import/netsurf/; revision=2
Diffstat (limited to 'render/css.c')
-rw-r--r-- | render/css.c | 545 |
1 files changed, 545 insertions, 0 deletions
diff --git a/render/css.c b/render/css.c new file mode 100644 index 000000000..45ed2d9bd --- /dev/null +++ b/render/css.c @@ -0,0 +1,545 @@ +/** + * $Id: css.c,v 1.1.1.1 2002/04/22 09:24:34 bursa Exp $ + */ + +#include <string.h> +#include <stdio.h> +#include <stdlib.h> +#include "css.h" +#include "utils.h" + +/** + * internal structures + */ + +struct rule { + struct css_selector * selector; + unsigned int selectors; + struct css_style * style; + struct rule * next; +}; + +struct decl { + unsigned long score; + struct rule * rule; +}; + +#define HASH_SIZE 13 + +struct css_stylesheet { + struct rule * hash[HASH_SIZE]; +}; + +static int parse_length(struct css_length * const length, const char *s); +static void parse_display(struct css_style * const style, const char * const value); +static void parse_float(struct css_style * const style, const char * const value); +static void parse_font_size(struct css_style * const style, const char * const value); +static void parse_height(struct css_style * const style, const char * const value); +static void parse_width(struct css_style * const style, const char * const value); +static void parse_property_list(struct css_style * style, char * str); +static void parse_selector(struct css_selector * sel, char * const str); +static unsigned int hash_str(const char * str); +static int seleq(const struct css_selector * const s1, const struct css_selector * const s2); +static unsigned long selmatch(const struct css_selector * const s, const struct css_selector * const sr); +static struct rule * find_rule(struct css_stylesheet * stylesheet, + struct css_selector * selector, unsigned int selectors); +static int cmpdecl(const struct decl * d0, const struct decl * d1); +static void update_style(struct css_stylesheet * stylesheet, struct css_selector * selector, + unsigned int selectors, char * str); +static void dump_length(const struct css_length * const length); +static void dump_selector(const struct css_selector * const sel); +static void dump_rule(const struct rule * rule); +static void css_dump_stylesheet(const struct css_stylesheet * stylesheet); + +/** + * property parsers + */ + +static int parse_length(struct css_length * const length, const char *s) +{ + length->unit = css_unit_parse(s + strspn(s, "0123456789+-.")); + if (length->unit == CSS_UNIT_UNKNOWN) return 1; + length->value = atof(s); + return 0; +} + +static void parse_display(struct css_style * const style, const char * const value) +{ + style->display = css_display_parse(value); +} + +static void parse_float(struct css_style * const style, const char * const value) +{ + style->float_ = css_float_parse(value); +} + +#define SIZE_FACTOR 1.2 + +static struct font_size { + const char * keyword; + float size; +} const font_size[] = { + { "xx-small", 1.0 / (SIZE_FACTOR * SIZE_FACTOR * SIZE_FACTOR) }, + { "x-small", 1.0 / (SIZE_FACTOR * SIZE_FACTOR) }, + { "small", 1.0 / SIZE_FACTOR }, + { "medium", 1.0 }, + { "large", 1.0 * SIZE_FACTOR }, + { "x-large", 1.0 * SIZE_FACTOR * SIZE_FACTOR }, + { "xx-large", 1.0 * SIZE_FACTOR * SIZE_FACTOR * SIZE_FACTOR } +}; + +static void parse_font_size(struct css_style * const style, const char * const value) +{ + unsigned int i; + for (i = 0; i < sizeof(font_size) / sizeof(struct font_size); i++) { + if (strcmp(value, font_size[i].keyword) == 0) { + style->font_size.size = CSS_FONT_SIZE_ABSOLUTE; + style->font_size.value.absolute = font_size[i].size; + return; + } + } + if (strcmp(value, "larger") == 0) + style->font_size.size = CSS_FONT_SIZE_PERCENT, + style->font_size.value.percent = SIZE_FACTOR * 100; + else if (strcmp(value, "smaller") == 0) + style->font_size.size = CSS_FONT_SIZE_PERCENT, + style->font_size.value.percent = 1 / SIZE_FACTOR * 100; + else if (strrchr(value, '%')) + style->font_size.size = CSS_FONT_SIZE_PERCENT, + style->font_size.value.percent = atof(value); + else if (parse_length(&style->font_size.value.length, value) == 0) + style->font_size.size = CSS_FONT_SIZE_LENGTH; +} + +static void parse_height(struct css_style * const style, const char * const value) +{ + if (strcmp(value, "auto") == 0) + style->height.height = CSS_HEIGHT_AUTO; + else if (parse_length(&style->height.length, value) == 0) + style->height.height = CSS_HEIGHT_LENGTH; +} + +static void parse_width(struct css_style * const style, const char * const value) +{ + if (strcmp(value, "auto") == 0) + style->width.width = CSS_WIDTH_AUTO; + else if (strrchr(value, '%')) + style->width.width = CSS_WIDTH_PERCENT, + style->width.value.percent = atof(value); + else if (parse_length(&style->width.value.length, value) == 0) + style->width.width = CSS_WIDTH_LENGTH; +} + +static struct property { + const char * const name; + void (*parse) (struct css_style * const s, const char * const value); +} const property[] = { + { "display", parse_display }, + { "float", parse_float }, + { "font-size", parse_font_size }, + { "height", parse_height }, + { "width", parse_width }, +}; + +/** + * parse a property list + */ + +static void parse_property_list(struct css_style * style, char * str) +{ + char * end; + for (; str != 0; str = end) { + char * prop; + char * value; + unsigned int i; + + if ((end = strchr(str, ';')) != 0) *end = 0, end++; + if ((value = strchr(str, ':')) == 0) continue; + *value = 0; value++; + prop = strip(str); + value = strip(value); + printf("css_parse: '%s' => '%s'\n", prop, value); + + for (i = 0; i < sizeof(property) / sizeof(struct property); i++) { + if (strcmp(prop, property[i].name) == 0) { + property[i].parse(style, value); + break; + } + } + } +} + +/** + * selectors + */ + +static void parse_selector(struct css_selector * sel, char * const str) +{ + char * dot = strchr(str, '.'); + char * hash = strchr(str, '#'); + + if ((dot == 0) && (hash == 0)) { + sel->element = xstrdup(str); + sel->class = sel->id = 0; + } else if (dot != 0) { + *dot = 0; + sel->element = xstrdup(str); + sel->class = xstrdup(dot + 1); + sel->id = 0; + } else if (hash != 0) { + *hash = 0; + sel->element = xstrdup(str); + sel->class = 0; + sel->id = xstrdup(hash + 1); + } +} + +/** + * stylesheet structure + */ + +static unsigned int hash_str(const char * str) +{ + unsigned int s = 0; + for (; *str != 0; str++) + s += *str; + return s % HASH_SIZE; +} + +static int seleq(const struct css_selector * const s1, const struct css_selector * const s2) +{ + return strcmp(s1->element, s2->element) == 0 && + ((s1->class == 0 && s2->class == 0) || + (s1->class != 0 && s2->class != 0 && strcmp(s1->class, s2->class) == 0)) && + ((s1->id == 0 && s2->id == 0) || + (s1->id != 0 && s2->id != 0 && strcmp(s1->id, s2->id) == 0)); +} + +static unsigned long selmatch(const struct css_selector * const s, const struct css_selector * const sr) +{ + unsigned int c; + if (strcmp(s->element, sr->element) != 0) return 0; + c = s->element[0] == 0 ? 0 : 1; + if (sr->class != 0) { + if (s->class != 0 && strcmp(s->class, sr->class) == 0) return 0x100 + c; + return 0; + } + if (sr->id != 0) { + if (s->id != 0 && strcmp(s->id, sr->id) == 0) return 0x10000 + c; + return 0; + } + return 1; +} + +struct css_stylesheet * css_new_stylesheet(void) +{ + struct css_stylesheet * stylesheet = xcalloc(1, sizeof(struct css_stylesheet)); + return stylesheet; +} + +static struct rule * find_rule(struct css_stylesheet * stylesheet, + struct css_selector * selector, unsigned int selectors) +{ + struct rule * rule; + for (rule = stylesheet->hash[hash_str(selector[selectors - 1].element)]; + rule != 0; rule = rule->next) { + unsigned int i; + if (selectors != rule->selectors) + continue; + /* inv: selector[0..i) == rule->selector[0..i) */ + for (i = 0; i != selectors && seleq(&selector[i], &rule->selector[i]); i++) + ; + if (i == selectors) + return rule; + } + return 0; +} + +static int cmpdecl(const struct decl * d0, const struct decl * d1) +{ + if (d0->score < d1->score) return -1; + else if (d0->score == d1->score) return 0; + return 1; +} + +void css_get_style(struct css_stylesheet * stylesheet, struct css_selector * selector, + unsigned int selectors, struct css_style * style) +{ + struct rule * rule; + struct decl * decl = xcalloc(0, sizeof(struct decl)); + unsigned int d, decls = 0; + + for (rule = stylesheet->hash[hash_str(selector[selectors - 1].element)]; + rule != 0; rule = rule->next) { + unsigned int i = selectors - 1; + unsigned int j; + unsigned int score, s; + + if ((score = selmatch(&selector[i], &rule->selector[rule->selectors - 1])) == 0) + continue; + if (selectors < rule->selectors) + continue; + + for (j = rule->selectors - 1; j != 0; j--) { + for (; i != 0 && (s = selmatch(&selector[i - 1], &rule->selector[j - 1])) == 0; i--) + ; + if (i == 0) + break; + score += s; + } + if (j == 0) { + decl = xrealloc(decl, (decls + 1) * sizeof(struct decl)); + decl[decls].score = score; + decl[decls].rule = rule; + decls++; + } + } + + qsort(decl, decls, sizeof(struct decl), (int (*) (const void *, const void *)) cmpdecl); + + for (d = 0; d < decls; d++) { +/* printf("%i: 0x%lx\n", d, decl[d].score); */ +/* css_dump_rule(decl[d].rule); */ + css_cascade(style, decl[d].rule->style); + } +} + +static void update_style(struct css_stylesheet * stylesheet, struct css_selector * selector, + unsigned int selectors, char * str) +{ + struct rule * rule = find_rule(stylesheet, selector, selectors); + if (rule == 0) { + unsigned int h = hash_str(selector[selectors - 1].element); + printf("update_style: not present - adding\n"); + rule = xcalloc(1, sizeof(struct rule)); + rule->selector = selector; + rule->selectors = selectors; + rule->style = xcalloc(1, sizeof(struct css_style)); + parse_property_list(rule->style, str); + rule->next = stylesheet->hash[h]; + stylesheet->hash[h] = rule; + } else { + printf("update_style: already present - updating\n"); + parse_property_list(rule->style, str); + free(selector); + } +} + +/** + * parse an entire css file or block + */ + +void css_parse_stylesheet(struct css_stylesheet * stylesheet, char * str) +{ + /* overwrite comments with spaces */ + char * copen = strstr(str, "/*"); + while (copen != 0) { + char * cclose = strstr(copen + 2, "*/"); + if (cclose == 0) { *copen = 0; break; } + memset(copen, ' ', (size_t) (cclose - copen + 2)); + copen = strstr(cclose + 2, "/*"); + } + + while (*str != 0) { + char * open = strchr(str, '{'); + char * close = strchr(str, '}'); + char * sels_str; + char * comma; + + if ((open == 0) || (close == 0)) break; + *open = 0; *close = 0; + + sels_str = strip(str); + do { + char * sel_str; + char * space; + char * style_str; + unsigned int selectors = 0; + struct css_selector * selector = xcalloc(0, sizeof(struct css_selector)); + + comma = strchr(sels_str, ','); + if (comma != 0) *comma = 0; + + sel_str = strip(sels_str); + printf("css_parse_stylesheet: %s\n", sel_str); + do { + space = strchr(sel_str, ' '); + if (space != 0) *space = 0; + selector = xrealloc(selector, sizeof(struct css_selector) * (selectors + 1)); + parse_selector(&selector[selectors++], sel_str); + if (space != 0) sel_str = strip(space + 1); + } while (space != 0); + + style_str = xstrdup(open + 1); + update_style(stylesheet, selector, selectors, style_str); + free(style_str); + + if (comma != 0) sels_str = strip(comma + 1); + } while (comma != 0); + + str = close + 1; + } +} + +/** + * dump a style + */ + +static void dump_length(const struct css_length * const length) +{ + printf("%g%s", length->value, + css_unit_name[length->unit]); +} + +void css_dump_style(const struct css_style * const style) +{ + puts("{"); + printf("\tdisplay: %s;\n", css_display_name[style->display]); + printf("\tfloat: %s;\n", css_float_name[style->float_]); + printf("\tfont-size: "); + switch (style->font_size.size) { + case CSS_FONT_SIZE_ABSOLUTE: printf("[%g]", style->font_size.value.absolute); break; + case CSS_FONT_SIZE_LENGTH: dump_length(&style->font_size.value.length); break; + case CSS_FONT_SIZE_PERCENT: printf("%g%%", style->font_size.value.percent); break; + case CSS_FONT_SIZE_INHERIT: printf("inherit"); break; + default: printf("UNKNOWN"); break; + } + puts(";"); + printf("\theight: "); + switch (style->height.height) { + case CSS_HEIGHT_AUTO: printf("auto"); break; + case CSS_HEIGHT_LENGTH: dump_length(&style->height.length); break; + default: printf("UNKNOWN"); break; + } + puts(";"); + printf("\twidth: "); + switch (style->width.width) { + case CSS_WIDTH_AUTO: printf("auto"); break; + case CSS_WIDTH_LENGTH: dump_length(&style->width.value.length); break; + case CSS_WIDTH_PERCENT: printf("%g%%", style->width.value.percent); break; + default: printf("UNKNOWN"); break; + } + puts(";"); + puts("}"); +} + +static void dump_selector(const struct css_selector * const sel) +{ + if (sel->class != 0) + printf("%s.%s ", sel->element, sel->class); + else if (sel->id != 0) + printf("%s#%s ", sel->element, sel->id); + else + printf("%s ", sel->element); +} + +static void dump_rule(const struct rule * rule) +{ + unsigned int i; + for (i = 0; i < rule->selectors; i++) + dump_selector(&rule->selector[i]); + css_dump_style(rule->style); +} + +static void css_dump_stylesheet(const struct css_stylesheet * stylesheet) +{ + unsigned int i; + for (i = 0; i < HASH_SIZE; i++) { + struct rule * rule; + printf("hash %i:\n", i); + for (rule = stylesheet->hash[i]; rule != 0; rule = rule->next) + dump_rule(rule); + } +} + +/** + * cascade styles + */ + +void css_cascade(struct css_style * const style, const struct css_style * const apply) +{ + float f; + style->display = apply->display; + style->float_ = apply->float_; + style->height = apply->height; + style->width = apply->width; + + /* font-size */ + f = apply->font_size.value.percent / 100; + switch (apply->font_size.size) { + case CSS_FONT_SIZE_ABSOLUTE: style->font_size = apply->font_size; break; + case CSS_FONT_SIZE_LENGTH: + switch (apply->font_size.value.length.unit) { + case CSS_UNIT_EM: f = apply->font_size.value.length.value; break; + case CSS_UNIT_EX: f = apply->font_size.value.length.value * 0.6 /*?*/; break; + default: style->font_size = apply->font_size; + } + if ((apply->font_size.value.length.unit != CSS_UNIT_EM) && + (apply->font_size.value.length.unit != CSS_UNIT_EX)) break; + /* drop through if EM or EX */ + case CSS_FONT_SIZE_PERCENT: + switch (style->font_size.size) { + case CSS_FONT_SIZE_ABSOLUTE: style->font_size.value.absolute *= f; break; + case CSS_FONT_SIZE_LENGTH: style->font_size.value.length.value *= f; break; + default: die("attempting percentage of unknown font-size"); + } + break; + case CSS_FONT_SIZE_INHERIT: + default: /* leave unchanged */ + } +} + +/** + * testing + */ +/* +int main(int argv, char *argc[]) +{ + int i; + struct rule * r; + struct css_stylesheet * s; + struct css_selector sel = { "h1", 0, 0 }; + struct css_selector con[] = {{ "html", 0, 0 }, {"body", 0, 0}, {"h1", "foo", 0}, {"b", 0, "bar"}}; + struct css_style * style = xcalloc(1, sizeof(struct css_style)); + + s = css_new_stylesheet(); + css_parse_stylesheet(s, argc[1]); + css_dump_stylesheet(s); + +/* r->selectors = 1; */ +/* css_stylesheet_add_rule(s, r); */ +/* puts("********** finding h1:"); + r = find_rule(s, &sel, 1); + if (r) + dump_rule(r); + else + puts("not found"); + + puts("********** finding html body h1.foo b#bar:"); + for (i = 1; i <= sizeof(con) / sizeof(con[0]); i++) { + css_get_style(s, con, i, style); + css_dump_style(style); + } + +/* printf("%x %x\n", r, r2); */ + +/* struct css_style *s; + struct css_selector *sel; + + s = parse_property_list(argc[1]); + css_dump_style(s); + + for (i = 2; i < argv; i++) { + css_cascade(s, parse_property_list(argc[i])); + css_dump_style(s); + }*/ + +/* for (i = 1; i < argv; i++) { + sel = parse_selector(argc[i]); + css_dump_selector(sel); + puts(""); + }*/ +/* + return 0; +} +*/ |