* This file is part of LyX, the document processor.
* Licence details can be found in the file COPYING.
*
- * \author Lars Gullik Bjønnes
+ * \author Lars Gullik Bjønnes
* \author Matthias Ettrich
* \author John Levon
*
#include <config.h>
#include "Length.h"
-#include "gettext.h"
-#include <string>
+#include "support/convert.h"
+#include "support/gettext.h"
+#include "support/lassert.h"
+#include "support/lstrings.h"
+using namespace std;
+using namespace lyx::support;
-namespace lyx {
-using std::string;
+namespace lyx {
// I am not sure if "mu" should be possible to select (Lgb)
// the latex units
char const * const unit_name[] = {
- "sp", "pt", "bp", "dd", "mm", "pc",
- "cc", "cm", "in", "ex", "em", "mu",
+ "bp", "cc", "cm", "dd", "em", "ex", "in", "mm", "mu",
+ "pc", "pt", "sp",
"text%", "col%", "page%", "line%",
- "theight%", "pheight%", "" };
+ "theight%", "pheight%", "baselineskip%", "" };
int const num_units = int(sizeof(unit_name) / sizeof(unit_name[0]) - 1);
// the LyX gui units
char const * const unit_name_gui[] = {
- N_("sp"), N_("pt"), N_("bp"), N_("dd"), N_("mm"), N_("pc"),
- N_("cc[[unit of measure]]"), N_("cm"), N_("in"), N_("ex"), N_("em"), N_("mu"),
- N_("Text Width %"), N_("Column Width %"), N_("Page Width %"), N_("Line Width %"),
- N_("Text Height %"), N_("Page Height %"), "" };
+ N_("bp"), N_("cc[[unit of measure]]"), N_("cm"), N_("dd"), N_("em"),
+ N_("ex"), N_("in[[unit of measure]]"), N_("mm"), N_("mu[[unit of measure]]"), N_("pc"),
+ N_("pt"), N_("sp"), N_("Text Width %"),
+ N_("Column Width %"), N_("Page Width %"), N_("Line Width %"),
+ N_("Text Height %"), N_("Page Height %"), N_("Line Distance %"), "" };
+
Length::UNIT unitFromString(string const & data)
{
}
+namespace {
+
+/// skip n characters of input
+inline void lyx_advance(string & data, size_t n)
+{
+ data.erase(0, n);
+}
+
+
+/// return true when the input is at the end
+inline bool isEndOfData(string const & data)
+{
+ return ltrim(data).empty();
+}
+
+
+/**
+ * nextToken - return the next token in the input
+ * @param data input string
+ * @param number_index the current position in the number array
+ * @param unit_index the current position in the unit array
+ * @return a char representing the type of token returned
+ *
+ * The possible return values are :
+ * + stretch indicator for glue length
+ * - shrink indicator for glue length
+ * n a numeric value (stored in number array)
+ * u a unit type (stored in unit array)
+ * E parse error
+ */
+char nextToken(string & data, double * number, int & number_index,
+ Length::UNIT * unit, int & unit_index)
+{
+ data = ltrim(data);
+
+ if (data.empty())
+ return '\0';
+
+ if (data[0] == '+') {
+ lyx_advance(data, 1);
+ return '+';
+ }
+
+ if (prefixIs(data, "plus")) {
+ lyx_advance(data, 4);
+ return '+';
+ }
+
+ if (data[0] == '-') {
+ lyx_advance(data, 1);
+ return '-';
+ }
+
+ if (prefixIs(data, "minus")) {
+ lyx_advance(data, 5);
+ return '-';
+ }
+
+ size_t i = data.find_first_not_of("0123456789.");
+
+ if (i != 0) {
+ if (number_index > 3)
+ return 'E';
+
+ string buffer;
+
+ // we have found some number
+ if (i == string::npos) {
+ buffer = data;
+ i = data.size() + 1;
+ } else {
+ buffer = data.substr(0, i);
+ }
+
+ lyx_advance(data, i);
+
+ if (isStrDbl(buffer)) {
+ number[number_index] = convert<double>(buffer);
+ ++number_index;
+ return 'n';
+ }
+ return 'E';
+ }
+
+ i = data.find_first_not_of("abcdefghijklmnopqrstuvwxyz%");
+ if (i != 0) {
+ if (unit_index > 3)
+ return 'E';
+
+ string buffer;
+
+ // we have found some alphabetical string
+ if (i == string::npos) {
+ buffer = data;
+ i = data.size() + 1;
+ } else {
+ buffer = data.substr(0, i);
+ }
+
+ // possibly we have "mmplus" string or similar
+ if (buffer.size() > 5 &&
+ (buffer.substr(2, 4) == string("plus") ||
+ buffer.substr(2, 5) == string("minus")))
+ {
+ lyx_advance(data, 2);
+ unit[unit_index] = unitFromString(buffer.substr(0, 2));
+ } else {
+ lyx_advance(data, i);
+ unit[unit_index] = unitFromString(buffer);
+ }
+
+ if (unit[unit_index] != Length::UNIT_NONE) {
+ ++unit_index;
+ return 'u';
+ }
+ return 'E'; // Error
+ }
+ return 'E'; // Error
+}
+
+
+/// latex representation of a vspace
+struct LaTeXLength {
+ char const * pattern;
+ int plus_val_index;
+ int minus_val_index;
+ int plus_uni_index;
+ int minus_uni_index;
+};
+
+
+/// the possible formats for a vspace string
+LaTeXLength table[] = {
+ { "nu", 0, 0, 0, 0 },
+ { "nu+nu", 2, 0, 2, 0 },
+ { "nu+nu-nu", 2, 3, 2, 3 },
+ { "nu+-nu", 2, 2, 2, 2 },
+ { "nu-nu", 0, 2, 0, 2 },
+ { "nu-nu+nu", 3, 2, 3, 2 },
+ { "nu-+nu", 2, 2, 2, 2 },
+ { "n+nu", 2, 0, 1, 0 },
+ { "n+n-nu", 2, 3, 1, 1 },
+ { "n+-nu", 2, 2, 1, 1 },
+ { "n-nu", 0, 2, 0, 1 },
+ { "n-n+nu", 3, 2, 1, 1 },
+ { "n-+nu", 2, 2, 1, 1 },
+ { "", 0, 0, 0, 0 } // sentinel, must be empty
+};
+
+
+} // namespace
+
+
+const char * stringFromUnit(int unit)
+{
+ if (unit < 0 || unit > num_units)
+ return 0;
+ return unit_name[unit];
+}
+
+
+bool isValidGlueLength(string const & data, GlueLength * result)
+{
+ // This parser is table-driven. First, it constructs a "pattern"
+ // that describes the sequence of tokens in "data". For example,
+ // "n-nu" means: number, minus sign, number, unit. As we go along,
+ // numbers and units are stored into static arrays. Then, "pattern"
+ // is searched in the "table". If it is found, the associated
+ // table entries tell us which number and unit should go where
+ // in the Length structure. Example: if "data" has the "pattern"
+ // "nu+nu-nu", the associated table entries are "2, 3, 2, 3".
+ // That means, "plus_val" is the second number that was seen
+ // in the input, "minus_val" is the third number, and "plus_uni"
+ // and "minus_uni" are the second and third units, respectively.
+ // ("val" and "uni" are always the first items seen in "data".)
+ // This is the most elegant solution I could find -- a straight-
+ // forward approach leads to very long, tedious code that would be
+ // much harder to understand and maintain. (AS)
+
+ if (data.empty()) {
+ if (result)
+ *result = GlueLength();
+ return true;
+ }
+ string buffer = ltrim(data);
+
+ // To make isValidGlueLength recognize negative values as
+ // the first number this little hack is needed:
+ int val_sign = 1; // positive as default
+ switch (buffer[0]) {
+ case '-':
+ lyx_advance(buffer, 1);
+ val_sign = -1;
+ break;
+ case '+':
+ lyx_advance(buffer, 1);
+ break;
+ default:
+ break;
+ }
+ // end of hack
+
+ // used to return numeric values in parsing vspace
+ double number[4] = { 0, 0, 0, 0 };
+ // used to return unit types in parsing vspace
+ Length::UNIT unit[4] = {Length::UNIT_NONE, Length::UNIT_NONE,
+ Length::UNIT_NONE, Length::UNIT_NONE};
+ int number_index = 1; // entries at index 0 are sentinels
+ int unit_index = 1; // entries at index 0 are sentinels
+
+ // construct "pattern" from "data"
+ size_t const pattern_max_size = 20;
+ string pattern;
+ while (!isEndOfData(buffer)) {
+ if (pattern.size() > pattern_max_size)
+ return false;
+ char const c = nextToken(buffer, number, number_index, unit,
+ unit_index);
+ if (c == 'E')
+ return false;
+ pattern.push_back(c);
+ }
+
+ // search "pattern" in "table"
+ size_t table_index = 0;
+ while (pattern != table[table_index].pattern) {
+ ++table_index;
+ if (!*table[table_index].pattern)
+ return false;
+ }
+
+ // Get the values from the appropriate places. If an index
+ // is zero, the corresponding array value is zero or UNIT_NONE,
+ // so we needn't check this.
+ if (result) {
+ result->len_.value (number[1] * val_sign);
+ result->len_.unit (unit[1]);
+ result->plus_.value (number[table[table_index].plus_val_index]);
+ result->plus_.unit (unit [table[table_index].plus_uni_index]);
+ result->minus_.value(number[table[table_index].minus_val_index]);
+ result->minus_.unit (unit [table[table_index].minus_uni_index]);
+ }
+ return true;
+}
+
+
+bool isValidLength(string const & data, Length * result)
+{
+ // This is a trimmed down version of isValidGlueLength.
+ // The parser may seem overkill for lengths without
+ // glue, but since we already have it, using it is
+ // easier than writing something from scratch.
+ if (data.empty()) {
+ if (result)
+ *result = Length();
+ return true;
+ }
+
+ string buffer = data;
+
+ // To make isValidLength recognize negative values
+ // this little hack is needed:
+ int val_sign = 1; // positive as default
+ switch (buffer[0]) {
+ case '-':
+ lyx_advance(buffer, 1);
+ val_sign = -1;
+ break;
+ case '+':
+ lyx_advance(buffer, 1);
+ // fall through
+ default:
+ // no action
+ break;
+ }
+ // end of hack
+
+ // used to return numeric values in parsing vspace
+ double number[4] = { 0, 0, 0, 0 };
+ // used to return unit types in parsing vspace
+ Length::UNIT unit[4] = {Length::UNIT_NONE, Length::UNIT_NONE,
+ Length::UNIT_NONE, Length::UNIT_NONE};
+ int number_index = 1; // entries at index 0 are sentinels
+ int unit_index = 1; // entries at index 0 are sentinels
+
+ // construct "pattern" from "data"
+ string pattern;
+ while (!isEndOfData(buffer)) {
+ if (pattern.size() > 2)
+ return false;
+ char const token = nextToken(buffer, number,
+ number_index, unit, unit_index);
+ if (token == 'E')
+ return false;
+ pattern += token;
+ }
+
+ // only the most basic pattern is accepted here
+ if (pattern != "nu")
+ return false;
+
+ // It _was_ a correct length string.
+ // Store away the values we found.
+ if (result) {
+ result->val_ = number[1] * val_sign;
+ result->unit_ = unit[1];
+ }
+ return true;
+}
+
} // namespace lyx