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-rw-r--r--source/html/css-apply.c875
1 files changed, 875 insertions, 0 deletions
diff --git a/source/html/css-apply.c b/source/html/css-apply.c
new file mode 100644
index 00000000..7f3028a9
--- /dev/null
+++ b/source/html/css-apply.c
@@ -0,0 +1,875 @@
+#include "mupdf/html.h"
+
+static void add_property(struct style *style, const char *name, struct value *value, int spec);
+
+struct rule *
+new_rule(struct selector *selector, struct property *declaration)
+{
+ struct rule *rule;
+
+ rule = malloc(sizeof(struct rule));
+ rule->selector = selector;
+ rule->declaration = declaration;
+ rule->next = NULL;
+
+ return rule;
+}
+
+struct selector *
+new_selector(const char *name)
+{
+ struct selector *sel;
+
+ sel = malloc(sizeof(struct selector));
+ sel->name = name ? strdup(name) : NULL;
+ sel->combine = 0;
+ sel->cond = NULL;
+ sel->left = NULL;
+ sel->right = NULL;
+ sel->next = NULL;
+
+ return sel;
+}
+
+struct condition *
+new_condition(int type, const char *key, const char *val)
+{
+ struct condition *cond;
+
+ cond = malloc(sizeof(struct condition));
+ cond->type = type;
+ cond->key = key ? strdup(key) : NULL;
+ cond->val = val ? strdup(val) : NULL;
+ cond->next = NULL;
+
+ return cond;
+}
+
+struct property *
+new_property(const char *name, struct value *value, int spec)
+{
+ struct property *prop;
+
+ prop = malloc(sizeof(struct property));
+ prop->name = strdup(name);
+ prop->value = value;
+ prop->spec = spec;
+ prop->next = NULL;
+
+ return prop;
+}
+
+struct value *
+new_value(int type, const char *data)
+{
+ struct value *val;
+
+ val = malloc(sizeof(struct value));
+ val->type = type;
+ val->data = strdup(data);
+ val->args = NULL;
+ val->next = NULL;
+
+ return val;
+}
+
+/*
+ * Compute specificity
+ */
+
+static int
+count_condition_ids(struct condition *cond)
+{
+ int n = 0;
+ while (cond)
+ {
+ if (cond->type == '#')
+ n ++;
+ cond = cond->next;
+ }
+ return n;
+}
+
+static int
+count_selector_ids(struct selector *sel)
+{
+ int n = count_condition_ids(sel->cond);
+ if (sel->left && sel->right)
+ {
+ n += count_selector_ids(sel->left);
+ n += count_selector_ids(sel->right);
+ }
+ return n;
+}
+
+static int
+count_condition_atts(struct condition *cond)
+{
+ int n = 0;
+ while (cond)
+ {
+ if (cond->type != '#' && cond->type != ':')
+ n ++;
+ cond = cond->next;
+ }
+ return n;
+}
+
+static int
+count_selector_atts(struct selector *sel)
+{
+ int n = count_condition_atts(sel->cond);
+ if (sel->left && sel->right)
+ {
+ n += count_selector_atts(sel->left);
+ n += count_selector_atts(sel->right);
+ }
+ return n;
+}
+
+static int
+count_condition_names(struct condition *cond)
+{
+ int n = 0;
+ while (cond)
+ {
+ if (cond->type == ':')
+ n ++;
+ cond = cond->next;
+ }
+ return n;
+}
+
+static int
+count_selector_names(struct selector *sel)
+{
+ int n = count_condition_names(sel->cond);
+ if (sel->left && sel->right)
+ {
+ n += count_selector_names(sel->left);
+ n += count_selector_names(sel->right);
+ }
+ else if (sel->name)
+ {
+ n ++;
+ }
+ return n;
+}
+
+int
+selector_specificity(struct selector *sel)
+{
+ int b = count_selector_ids(sel);
+ int c = count_selector_atts(sel);
+ int d = count_selector_names(sel);
+ return b * 100 + c * 10 + d;
+}
+
+/*
+ * Pretty printing
+ */
+
+void
+print_value(struct value *val)
+{
+ printf("%s", val->data);
+ if (val->args)
+ {
+ printf("(");
+ print_value(val->args);
+ printf(")");
+ }
+ if (val->next)
+ {
+ printf(" ");
+ print_value(val->next);
+ }
+}
+
+void
+print_property(struct property *prop)
+{
+ printf("\t%s: ", prop->name);
+ print_value(prop->value);
+ printf(" !%d;\n", prop->spec);
+}
+
+void
+print_condition(struct condition *cond)
+{
+ if (cond->type == '=')
+ printf("[%s=%s]", cond->key, cond->val);
+ else if (cond->type == '[')
+ printf("[%s]", cond->key);
+ else
+ printf("%c%s", cond->type, cond->val);
+ if (cond->next)
+ print_condition(cond->next);
+}
+
+void
+print_selector(struct selector *sel)
+{
+ if (sel->combine)
+ {
+putchar('(');
+ print_selector(sel->left);
+ if (sel->combine == ' ')
+ printf(" ");
+ else
+ printf(" %c ", sel->combine);
+ print_selector(sel->right);
+putchar(')');
+ }
+ else if (sel->name)
+ printf("%s", sel->name);
+ else
+ printf("*");
+ if (sel->cond)
+ {
+ print_condition(sel->cond);
+ }
+}
+
+void
+print_rule(struct rule *rule)
+{
+ struct selector *sel;
+ struct property *prop;
+
+ for (sel = rule->selector; sel; sel = sel->next)
+ {
+ print_selector(sel);
+ printf(" !%d", selector_specificity(sel));
+ if (sel->next)
+ printf(", ");
+ }
+
+ printf("\n{\n");
+ for (prop = rule->declaration; prop; prop = prop->next)
+ {
+ print_property(prop);
+ }
+ printf("}\n");
+}
+
+void
+print_rules(struct rule *rule)
+{
+ while (rule)
+ {
+ print_rule(rule);
+ rule = rule->next;
+ }
+}
+
+/*
+ * Selector matching
+ */
+
+int
+match_id_condition(fz_xml *node, const char *p)
+{
+ const char *s = fz_xml_att(node, "id");
+ if (s && !strcmp(s, p))
+ return 1;
+ return 0;
+}
+
+int
+match_class_condition(fz_xml *node, const char *p)
+{
+ const char *s = fz_xml_att(node, "class");
+ char buf[1024];
+ if (s) {
+ strcpy(buf, s);
+ s = strtok(buf, " ");
+ while (s) {
+ if (!strcmp(s, p))
+ return 1;
+ s = strtok(NULL, " ");
+ }
+ }
+ return 0;
+}
+
+int
+match_condition(struct condition *cond, fz_xml *node)
+{
+ if (!cond)
+ return 1;
+
+ switch (cond->type) {
+ default: return 0;
+ case ':': return 0; /* don't support pseudo-classes */
+ case '#': if (!match_id_condition(node, cond->val)) return 0; break;
+ case '.': if (!match_class_condition(node, cond->val)) return 0; break;
+ }
+
+ return match_condition(cond->next, node);
+}
+
+int
+match_selector(struct selector *sel, fz_xml *node)
+{
+ if (!node)
+ return 0;
+
+ if (sel->combine)
+ {
+ /* descendant */
+ if (sel->combine == ' ')
+ {
+ fz_xml *parent = fz_xml_up(node);
+ while (parent)
+ {
+ if (match_selector(sel->left, parent))
+ if (match_selector(sel->right, node))
+ return 1;
+ parent = fz_xml_up(parent);
+ }
+ return 0;
+ }
+
+ /* child */
+ if (sel->combine == '>')
+ {
+ fz_xml *parent = fz_xml_up(node);
+ if (!parent)
+ return 0;
+ if (!match_selector(sel->left, parent))
+ return 0;
+ if (!match_selector(sel->right, node))
+ return 0;
+ }
+
+ /* adjacent */
+ if (sel->combine == '+')
+ {
+ fz_xml *prev = fz_xml_prev(node);
+ while (prev && !fz_xml_tag(prev) && fz_xml_prev(prev))
+ prev = fz_xml_prev(prev);
+ if (!prev)
+ return 0;
+ if (!fz_xml_tag(prev))
+ return 0;
+ if (!match_selector(sel->left, prev))
+ return 0;
+ if (!match_selector(sel->right, node))
+ return 0;
+ }
+ }
+
+ if (sel->name)
+ {
+ if (strcmp(sel->name, fz_xml_tag(node)))
+ return 0;
+ }
+
+ if (sel->cond)
+ {
+ if (!match_condition(sel->cond, node))
+ return 0;
+ }
+
+ return 1;
+}
+
+/*
+ * Annotating nodes with properties and expanding shorthand forms.
+ */
+
+static int
+count_values(struct value *value)
+{
+ int n = 0;
+ while (value)
+ {
+ n++;
+ value = value->next;
+ }
+ return n;
+}
+
+static void
+add_shorthand_margin(struct style *style, struct value *value, int spec)
+{
+ int n = count_values(value);
+
+ if (n == 1)
+ {
+ add_property(style, "margin-top", value, spec);
+ add_property(style, "margin-right", value, spec);
+ add_property(style, "margin-bottom", value, spec);
+ add_property(style, "margin-left", value, spec);
+ }
+
+ if (n == 2)
+ {
+ struct value *a = new_value(value->type, value->data);
+ struct value *b = new_value(value->next->type, value->next->data);
+
+ add_property(style, "margin-top", a, spec);
+ add_property(style, "margin-right", b, spec);
+ add_property(style, "margin-bottom", a, spec);
+ add_property(style, "margin-left", b, spec);
+ }
+
+ if (n == 3)
+ {
+ struct value *a = new_value(value->type, value->data);
+ struct value *b = new_value(value->next->type, value->next->data);
+ struct value *c = new_value(value->next->next->type, value->next->next->data);
+
+ add_property(style, "margin-top", a, spec);
+ add_property(style, "margin-right", b, spec);
+ add_property(style, "margin-bottom", c, spec);
+ add_property(style, "margin-left", b, spec);
+ }
+
+ if (n == 4)
+ {
+ struct value *a = new_value(value->type, value->data);
+ struct value *b = new_value(value->next->type, value->next->data);
+ struct value *c = new_value(value->next->next->type, value->next->next->data);
+ struct value *d = new_value(value->next->next->next->type, value->next->next->next->data);
+
+ add_property(style, "margin-top", a, spec);
+ add_property(style, "margin-right", b, spec);
+ add_property(style, "margin-bottom", c, spec);
+ add_property(style, "margin-left", d, spec);
+ }
+}
+
+static void
+add_shorthand_padding(struct style *style, struct value *value, int spec)
+{
+ int n = count_values(value);
+
+ if (n == 1)
+ {
+ add_property(style, "padding-top", value, spec);
+ add_property(style, "padding-right", value, spec);
+ add_property(style, "padding-bottom", value, spec);
+ add_property(style, "padding-left", value, spec);
+ }
+
+ if (n == 2)
+ {
+ struct value *a = new_value(value->type, value->data);
+ struct value *b = new_value(value->next->type, value->next->data);
+
+ add_property(style, "padding-top", a, spec);
+ add_property(style, "padding-right", b, spec);
+ add_property(style, "padding-bottom", a, spec);
+ add_property(style, "padding-left", b, spec);
+ }
+
+ if (n == 3)
+ {
+ struct value *a = new_value(value->type, value->data);
+ struct value *b = new_value(value->next->type, value->next->data);
+ struct value *c = new_value(value->next->next->type, value->next->next->data);
+
+ add_property(style, "padding-top", a, spec);
+ add_property(style, "padding-right", b, spec);
+ add_property(style, "padding-bottom", c, spec);
+ add_property(style, "padding-left", b, spec);
+ }
+
+ if (n == 4)
+ {
+ struct value *a = new_value(value->type, value->data);
+ struct value *b = new_value(value->next->type, value->next->data);
+ struct value *c = new_value(value->next->next->type, value->next->next->data);
+ struct value *d = new_value(value->next->next->next->type, value->next->next->next->data);
+
+ add_property(style, "padding-top", a, spec);
+ add_property(style, "padding-right", b, spec);
+ add_property(style, "padding-bottom", c, spec);
+ add_property(style, "padding-left", d, spec);
+ }
+}
+
+static void
+add_shorthand_border_width(struct style *style, struct value *value, int spec)
+{
+ int n = count_values(value);
+
+ if (n == 1)
+ {
+ add_property(style, "border-top-width", value, spec);
+ add_property(style, "border-right-width", value, spec);
+ add_property(style, "border-bottom-width", value, spec);
+ add_property(style, "border-left-width", value, spec);
+ }
+
+ if (n == 2)
+ {
+ struct value *a = new_value(value->type, value->data);
+ struct value *b = new_value(value->next->type, value->next->data);
+
+ add_property(style, "border-top-width", a, spec);
+ add_property(style, "border-right-width", b, spec);
+ add_property(style, "border-bottom-width", a, spec);
+ add_property(style, "border-left-width", b, spec);
+ }
+
+ if (n == 3)
+ {
+ struct value *a = new_value(value->type, value->data);
+ struct value *b = new_value(value->next->type, value->next->data);
+ struct value *c = new_value(value->next->next->type, value->next->next->data);
+
+ add_property(style, "border-top-width", a, spec);
+ add_property(style, "border-right-width", b, spec);
+ add_property(style, "border-bottom-width", c, spec);
+ add_property(style, "border-left-width", b, spec);
+ }
+
+ if (n == 4)
+ {
+ struct value *a = new_value(value->type, value->data);
+ struct value *b = new_value(value->next->type, value->next->data);
+ struct value *c = new_value(value->next->next->type, value->next->next->data);
+ struct value *d = new_value(value->next->next->next->type, value->next->next->next->data);
+
+ add_property(style, "border-top-width", a, spec);
+ add_property(style, "border-right-width", b, spec);
+ add_property(style, "border-bottom-width", c, spec);
+ add_property(style, "border-left-width", d, spec);
+ }
+}
+
+static void
+add_property(struct style *style, const char *name, struct value *value, int spec)
+{
+ int i;
+
+ if (!strcmp(name, "margin"))
+ {
+ add_shorthand_margin(style, value, spec);
+ return;
+ }
+ if (!strcmp(name, "padding"))
+ {
+ add_shorthand_padding(style, value, spec);
+ return;
+ }
+ if (!strcmp(name, "border-width"))
+ {
+ add_shorthand_border_width(style, value, spec);
+ return;
+ }
+
+ /* TODO: border-color */
+ /* TODO: border-style */
+ /* TODO: border */
+ /* TODO: font */
+ /* TODO: list-style */
+ /* TODO: background */
+
+ for (i = 0; i < style->count; ++i)
+ {
+ if (!strcmp(style->prop[i].name, name))
+ {
+ if (style->prop[i].spec <= spec)
+ {
+ style->prop[i].value = value;
+ style->prop[i].spec = spec;
+ }
+ return;
+ }
+ }
+
+ if (style->count + 1 >= nelem(style->prop))
+ {
+ // fz_warn(ctx, "too many css properties");
+ return;
+ }
+
+ style->prop[style->count].name = name;
+ style->prop[style->count].value = value;
+ style->prop[style->count].spec = spec;
+ ++style->count;
+}
+
+void
+apply_styles(struct rule *rule, struct style *style, fz_xml *node)
+{
+ struct selector *sel;
+ struct property *prop;
+
+ while (rule)
+ {
+ sel = rule->selector;
+ while (sel)
+ {
+ if (match_selector(sel, node))
+ {
+ for (prop = rule->declaration; prop; prop = prop->next)
+ add_property(style, prop->name, prop->value, selector_specificity(sel));
+ break;
+ }
+ sel = sel->next;
+ }
+ rule = rule->next;
+ }
+}
+
+static const char *inherit_list[] = {
+ "color", "direction",
+ "font-family", "font-size", "font-style", "font-variant", "font-weight",
+ "letter-spacing", "line-height",
+ "list-style-image", "list-style-position", "list-style-type",
+ "orphans", "quotes", "text-align", "text-indent", "text-transform",
+ "visibility", "white-space", "widows", "word-spacing",
+
+ /* this is not supposed to be inherited: */
+ "vertical-align",
+};
+
+static struct value *
+get_raw_property(struct style *node, const char *name)
+{
+ int i;
+ for (i = 0; i < node->count; ++i)
+ if (!strcmp(node->prop[i].name, name))
+ return node->prop[i].value;
+ return NULL;
+}
+
+static int
+should_inherit_property(const char *name)
+{
+ int l = 0;
+ int r = nelem(inherit_list) - 1;
+ while (l <= r)
+ {
+ int m = (l + r) >> 1;
+ int c = strcmp(name, inherit_list[m]);
+ if (c < 0)
+ r = m - 1;
+ else if (c > 0)
+ l = m + 1;
+ else
+ return 1;
+ }
+ return 0;
+}
+
+static struct value *
+get_style_property(struct style *node, const char *name)
+{
+ struct value *value;
+
+ value = get_raw_property(node, name);
+ if (node->up)
+ {
+ if (value && !strcmp(value->data, "inherit"))
+ return get_style_property(node->up, name);
+ if (!value && should_inherit_property(name))
+ return get_style_property(node->up, name);
+ }
+ return value;
+}
+
+static const char *
+get_style_property_string(struct style *node, const char *name, const char *initial)
+{
+ struct value *value;
+ value = get_style_property(node, name);
+ if (!value)
+ return initial;
+ return value->data;
+}
+
+static int
+compute_number(struct value *value, int em, int hundred, int scale, int initial)
+{
+ char *p;
+
+ if (!value)
+ return initial;
+
+ if (value->type == CSS_PERCENT)
+ return strtof(value->data, &p) * hundred / 100;
+
+ if (value->type == CSS_NUMBER)
+ return strtof(value->data, &p) * scale;
+
+ if (value->type == CSS_LENGTH)
+ {
+ float x = strtof(value->data, &p);
+
+ if (p[0] == 'e' && p[1] == 'm')
+ return x * em;
+ if (p[0] == 'e' && p[1] == 'x')
+ return x * em / 2;
+
+ if (p[0] == 'i' && p[1] == 'n')
+ return x * 72;
+ if (p[0] == 'c' && p[1] == 'm')
+ return x * 72 / 2.54;
+ if (p[0] == 'm' && p[1] == 'm')
+ return x * 72 / 25.4;
+ if (p[0] == 'p' && p[1] == 'c')
+ return x * 12;
+
+ if (p[0] == 'p' && p[1] == 't')
+ return x;
+ if (p[0] == 'p' && p[1] == 'x')
+ return x;
+
+ return x;
+ }
+
+ return initial;
+}
+
+void
+compute_style(struct computed_style *style, struct style *node)
+{
+ struct value *value;
+ int em = 12;
+ int hundred = 100;
+
+ memset(style, 0, sizeof *style);
+
+ style->display = INLINE;
+ style->position = STATIC;
+ style->text_align = LEFT;
+ style->font_size = 12;
+
+ value = get_style_property(node, "display");
+ if (value)
+ {
+ if (!strcmp(value->data, "none"))
+ style->display = NONE;
+ if (!strcmp(value->data, "inline"))
+ style->display = INLINE;
+ if (!strcmp(value->data, "block"))
+ style->display = BLOCK;
+ if (!strcmp(value->data, "list-item"))
+ style->display = LIST_ITEM;
+ }
+
+ value = get_style_property(node, "position");
+ if (value)
+ {
+ if (!strcmp(value->data, "static"))
+ style->position = STATIC;
+ if (!strcmp(value->data, "relative"))
+ style->position = RELATIVE;
+ if (!strcmp(value->data, "absolute"))
+ style->position = ABSOLUTE;
+ if (!strcmp(value->data, "fixed"))
+ style->position = FIXED;
+ }
+
+ value = get_style_property(node, "text-align");
+ if (value)
+ {
+ if (!strcmp(value->data, "left"))
+ style->text_align = LEFT;
+ if (!strcmp(value->data, "right"))
+ style->text_align = RIGHT;
+ if (!strcmp(value->data, "center"))
+ style->text_align = CENTER;
+ if (!strcmp(value->data, "justify"))
+ style->text_align = JUSTIFY;
+ }
+
+ value = get_style_property(node, "vertical-align");
+ if (value)
+ {
+ if (!strcmp(value->data, "super"))
+ style->vertical_align = 1;
+ if (!strcmp(value->data, "sub"))
+ style->vertical_align = -1;
+ }
+
+ value = get_style_property(node, "font-size");
+ if (value) {
+ if (!strcmp(value->data, "xx-large")) style->font_size = 20;
+ else if (!strcmp(value->data, "x-large")) style->font_size = 16;
+ else if (!strcmp(value->data, "large")) style->font_size = 14;
+ else if (!strcmp(value->data, "medium")) style->font_size = 12;
+ else if (!strcmp(value->data, "small")) style->font_size = 10;
+ else if (!strcmp(value->data, "x-small")) style->font_size = 8;
+ else if (!strcmp(value->data, "xx-small")) style->font_size = 6;
+ else if (!strcmp(value->data, "larger")) style->font_size = em + 2;
+ else if (!strcmp(value->data, "smaller")) style->font_size = em - 2;
+ else style->font_size = compute_number(value, em, em, 1, 12);
+ } else {
+ style->font_size = 12;
+ }
+ em = style->font_size;
+
+ value = get_style_property(node, "line-height");
+ style->line_height = compute_number(value, em, em, em, 1.2 * em);
+
+ value = get_style_property(node, "text-indent");
+ style->text_indent = compute_number(value, em, hundred, 1, 0);
+
+ value = get_style_property(node, "margin-top");
+ style->margin[0] = compute_number(value, em, hundred, 1, 0);
+ value = get_style_property(node, "margin-right");
+ style->margin[1] = compute_number(value, em, hundred, 1, 0);
+ value = get_style_property(node, "margin-bottom");
+ style->margin[2] = compute_number(value, em, hundred, 1, 0);
+ value = get_style_property(node, "margin-left");
+ style->margin[3] = compute_number(value, em, hundred, 1, 0);
+
+ value = get_style_property(node, "padding-top");
+ style->padding[0] = compute_number(value, em, hundred, 1, 0);
+ value = get_style_property(node, "padding-right");
+ style->padding[1] = compute_number(value, em, hundred, 1, 0);
+ value = get_style_property(node, "padding-bottom");
+ style->padding[2] = compute_number(value, em, hundred, 1, 0);
+ value = get_style_property(node, "padding-left");
+ style->padding[3] = compute_number(value, em, hundred, 1, 0);
+
+ {
+ const char *font_family = get_style_property_string(node, "font-family", "serif");
+ const char *font_variant = get_style_property_string(node, "font-variant", "normal");
+ const char *font_style = get_style_property_string(node, "font-style", "normal");
+ const char *font_weight = get_style_property_string(node, "font-weight", "normal");
+
+ style->font_family = font_family;
+
+ style->smallcaps = 0;
+ if (!strcmp(font_variant, "small-caps"))
+ style->smallcaps = 1;
+
+ style->italic = 0;
+ if (!strcmp(font_style, "italic") || !strcmp(font_style, "oblique"))
+ style->italic = 1;
+
+ style->bold = 0;
+ if (!strcmp(font_weight, "bold") || !strcmp(font_weight, "bolder") || atoi(font_weight) > 400)
+ style->bold = 1;
+ }
+}
+
+void
+print_style(struct computed_style *style)
+{
+ printf("style {\n");
+ printf("\tdisplay = %d;\n", style->display);
+ printf("\tposition = %d;\n", style->position);
+ printf("\ttext-align = %d;\n", style->text_align);
+ printf("\tfont-family = %s;\n", style->font_family);
+ printf("\tfont-weight = %s;\n", style->bold ? "bold" : "normal");
+ printf("\tfont-style = %s;\n", style->italic ? "italic" : "normal");
+ printf("\tfont-variant = %s;\n", style->smallcaps ? "small-caps" : "normal");
+ printf("\tfont-size = %d;\n", style->font_size);
+ printf("\tline-height = %d;\n", style->line_height);
+ printf("\ttext-indent = %d;\n", style->text_indent);
+ printf("\tvertical-align = %d;\n", style->vertical_align);
+ printf("\tmargin = %d %d %d %d;\n",
+ style->margin[0], style->margin[1], style->margin[2], style->margin[3]);
+ printf("\tpadding = %d %d %d %d;\n",
+ style->padding[0], style->padding[1], style->padding[2], style->padding[3]);
+ printf("}\n");
+}
generated by cgit v1.2.3 (git 2.25.1) at 2025-04-11 08:18:21 +0000