1 files changed, 266 insertions, 0 deletions
diff --git a/src/mp-equation-parser.y b/src/mp-equation-parser.y
new file mode 100644
index 0000000..064f90f
--- /dev/null
+++ b/src/mp-equation-parser.y
@@ -0,0 +1,266 @@
+%{
+/*  Copyright (c) 2004-2008 Sami Pietila
+ *  Copyright (c) 2008-2009 Robert Ancell
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2, or (at your option)
+ *  any later version.
+ *
+ *  This program 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
+ *  General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to the Free Software
+ *  Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
+ *  02111-1307, USA.
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <math.h>
+#include <errno.h>
+#include <assert.h>
+
+#include "mp-equation-private.h"
+#include "mp-equation-parser.h"
+#include "mp-equation-lexer.h"
+
+// fixme support x log x
+// treat exp NAME exp as a function always and pass both arguments, i.e.
+// can do mod using both and all others use $1 * NAME($3)
+
+static void set_error(yyscan_t yyscanner, int error, const char *token)
+{
+    _mp_equation_get_extra(yyscanner)->error = error;
+    if (token)
+        _mp_equation_get_extra(yyscanner)->error_token = strdup(token);
+}
+
+static void set_result(yyscan_t yyscanner, const MPNumber *x)
+{
+    mp_set_from_mp(x, &(_mp_equation_get_extra(yyscanner))->ret);
+}
+
+static char *
+utf8_next_char (const char *c)
+{
+    c++;
+    while ((*c & 0xC0) == 0x80)
+        c++;
+    return (char *)c;
+}
+
+static int get_variable(yyscan_t yyscanner, const char *name, int power, MPNumber *z)
+{
+    int result = 0;
+
+    /* If defined, then get the variable */
+    if (_mp_equation_get_extra(yyscanner)->get_variable(_mp_equation_get_extra(yyscanner), name, z)) {
+        mp_xpowy_integer(z, power, z);
+        return 1;
+    }
+    
+    /* If has more than one character then assume a multiplication of variables */
+    if (utf8_next_char(name)[0] != '\0') {
+        const char *c, *next;
+        char *buffer = malloc(sizeof(char) * strlen(name));
+        MPNumber value;
+
+        result = 1;
+        mp_set_from_integer(1, &value);
+        for (c = name; *c != '\0'; c = next) {
+            MPNumber t;
+
+            next = utf8_next_char(c);
+            snprintf(buffer, next - c + 1, "%s", c);
+
+            if (!_mp_equation_get_extra(yyscanner)->get_variable(_mp_equation_get_extra(yyscanner), buffer, &t)) {
+                result = 0;
+                break;
+            }
+
+            /* If last term do power */
+            if (*next == '\0')
+                mp_xpowy_integer(&t, power, &t);
+
+            mp_multiply(&value, &t, &value);
+        }
+
+        free(buffer);
+        if (result)
+            mp_set_from_mp(&value, z);
+    }
+
+    if (!result)
+        set_error(yyscanner, PARSER_ERR_UNKNOWN_VARIABLE, name);
+
+    return result;
+}
+
+static void set_variable(yyscan_t yyscanner, const char *name, MPNumber *x)
+{
+    _mp_equation_get_extra(yyscanner)->set_variable(_mp_equation_get_extra(yyscanner), name, x);
+}
+
+static int get_function(yyscan_t yyscanner, const char *name, const MPNumber *x, MPNumber *z)
+{
+    if (!_mp_equation_get_extra(yyscanner)->get_function(_mp_equation_get_extra(yyscanner), name, x, z)) {
+        set_error(yyscanner, PARSER_ERR_UNKNOWN_FUNCTION, name);
+        return 0;
+    }
+    return 1;
+}
+
+static int get_inverse_function(yyscan_t yyscanner, const char *name, const MPNumber *x, MPNumber *z)
+{
+    char *inv_name;
+    int result;
+    
+    inv_name = malloc(sizeof(char) * (strlen(name) + strlen("⁻¹") + 1));
+    strcpy(inv_name, name);
+    strcat(inv_name, "⁻¹");
+    result = get_function(yyscanner, inv_name, x, z);
+    free(inv_name);
+
+    return result;
+}
+
+static void do_not(yyscan_t yyscanner, const MPNumber *x, MPNumber *z)
+{
+    if (!mp_is_overflow(x, _mp_equation_get_extra(yyscanner)->options->wordlen)) {
+        set_error(yyscanner, PARSER_ERR_OVERFLOW, NULL);
+    }
+    mp_not(x, _mp_equation_get_extra(yyscanner)->options->wordlen, z);
+}
+
+static char *make_unit(const char *name, int power)
+{
+    char *name2;
+
+    // FIXME: Hacky
+    if (power == 2) {
+        name2 = malloc(sizeof(char) * (strlen(name) + strlen("²") + 1));
+        sprintf(name2, "%s²", name);
+    }
+    else if (power == 3) {
+        name2 = malloc(sizeof(char) * (strlen(name) + strlen("³") + 1));
+        sprintf(name2, "%s³", name);
+    }
+    else {
+        name2 = malloc(sizeof(char) * (strlen(name) + strlen("?") + 1));
+        sprintf(name2, "%s?", name);
+    }
+    
+    return name2;
+}
+
+static void do_conversion(yyscan_t yyscanner, const MPNumber *x, const char *x_units, const char *z_units, MPNumber *z)
+{
+    if (!_mp_equation_get_extra(yyscanner)->convert(_mp_equation_get_extra(yyscanner), x, x_units, z_units, z))
+        set_error(yyscanner, PARSER_ERR_UNKNOWN_CONVERSION, NULL);
+}
+
+%}
+
+%pure-parser
+%name-prefix="_mp_equation_"
+%locations
+%parse-param {yyscan_t yyscanner}
+%lex-param {yyscan_t yyscanner}
+
+%union {
+  MPNumber int_t;
+  int integer;
+  char *name;
+}
+
+%left <int_t> tNUMBER
+%left tLFLOOR tRFLOOR tLCEILING tRCEILING
+%left UNARY_PLUS
+%left tADD tSUBTRACT
+%left tAND tOR tXOR tXNOR
+%left tMULTIPLY tDIVIDE tMOD MULTIPLICATION
+%left tNOT
+%left tROOT tROOT3 tROOT4
+%left <name> tVARIABLE tFUNCTION
+%right <integer> tSUBNUM tSUPNUM tNSUPNUM
+%left BOOLEAN_OPERATOR
+%left PERCENTAGE
+%left UNARY_MINUS
+%right '^' '!' '|'
+%left tIN
+
+%type <int_t> exp variable term
+%type <name> unit
+%start statement
+
+%%
+
+statement:
+  exp { set_result(yyscanner, &$1); }
+| exp '=' { set_result(yyscanner, &$1); }
+| tVARIABLE '=' exp {set_variable(yyscanner, $1, &$3); set_result(yyscanner, &$3); }
+| tNUMBER unit tIN unit { MPNumber t; do_conversion(yyscanner, &$1, $2, $4, &t); set_result(yyscanner, &t); free($2); free($4); }
+| unit tIN unit { MPNumber x, t; mp_set_from_integer(1, &x); do_conversion(yyscanner, &x, $1, $3, &t); set_result(yyscanner, &t); free($1); free($3); }
+;
+
+unit:
+  tVARIABLE {$$ = $1;}
+| tVARIABLE tSUPNUM {$$ = make_unit($1, $2); free($1);}
+
+/* |x| gets confused and thinks = |x|(...||) */
+
+exp:
+  '(' exp ')' {mp_set_from_mp(&$2, &$$);}
+| exp '(' exp ')' {mp_multiply(&$1, &$3, &$$);}
+| tLFLOOR exp tRFLOOR {mp_floor(&$2, &$$);}
+| tLCEILING exp tRCEILING {mp_ceiling(&$2, &$$);}
+| '[' exp ']' {mp_round(&$2, &$$);}
+| '{' exp '}' {mp_fractional_part(&$2, &$$);}
+| '|' exp '|' {mp_abs(&$2, &$$);}
+| exp '^' exp {mp_xpowy(&$1, &$3, &$$);}
+| exp tSUPNUM {mp_xpowy_integer(&$1, $2, &$$);}
+| exp tNSUPNUM {mp_xpowy_integer(&$1, $2, &$$);}
+| exp '!' {mp_factorial(&$1, &$$);}
+| variable {mp_set_from_mp(&$1, &$$);}
+| tNUMBER variable %prec MULTIPLICATION {mp_multiply(&$1, &$2, &$$);}
+| tSUBTRACT exp %prec UNARY_MINUS {mp_invert_sign(&$2, &$$);}
+| tADD tNUMBER %prec UNARY_PLUS {mp_set_from_mp(&$2, &$$);}
+| exp tDIVIDE exp {mp_divide(&$1, &$3, &$$);}
+| exp tMOD exp {mp_modulus_divide(&$1, &$3, &$$);}
+| exp tMULTIPLY exp {mp_multiply(&$1, &$3, &$$);}
+| exp tADD exp '%' %prec PERCENTAGE {mp_add_integer(&$3, 100, &$3); mp_divide_integer(&$3, 100, &$3); mp_multiply(&$1, &$3, &$$);}
+| exp tSUBTRACT exp '%' %prec PERCENTAGE {mp_add_integer(&$3, -100, &$3); mp_divide_integer(&$3, -100, &$3); mp_multiply(&$1, &$3, &$$);}
+| exp tADD exp {mp_add(&$1, &$3, &$$);}
+| exp tSUBTRACT exp {mp_subtract(&$1, &$3, &$$);}
+| exp '%' {mp_divide_integer(&$1, 100, &$$);}
+| tNOT exp {do_not(yyscanner, &$2, &$$);}
+| exp tAND exp %prec BOOLEAN_OPERATOR {mp_and(&$1, &$3, &$$);}
+| exp tOR exp %prec BOOLEAN_OPERATOR {mp_or(&$1, &$3, &$$);}
+| exp tXOR exp %prec BOOLEAN_OPERATOR {mp_xor(&$1, &$3, &$$);}
+| tNUMBER {mp_set_from_mp(&$1, &$$);}
+;
+
+
+variable:
+  term {mp_set_from_mp(&$1, &$$);}
+| tFUNCTION exp {if (!get_function(yyscanner, $1, &$2, &$$)) YYABORT; free($1);}
+| tFUNCTION tSUPNUM exp {if (!get_function(yyscanner, $1, &$3, &$$)) YYABORT; mp_xpowy_integer(&$$, $2, &$$); free($1);}
+| tFUNCTION tNSUPNUM exp {if (!get_inverse_function(yyscanner, $1, &$3, &$$)) YYABORT; mp_xpowy_integer(&$$, -$2, &$$); free($1);}
+| tVARIABLE tSUPNUM exp {set_error(yyscanner, PARSER_ERR_UNKNOWN_FUNCTION, $1); free($1); YYABORT;}
+| tSUBNUM tROOT exp {mp_root(&$3, $1, &$$);}
+| tROOT exp {mp_sqrt(&$2, &$$);}
+| tROOT3 exp {mp_root(&$2, 3, &$$);}
+| tROOT4 exp {mp_root(&$2, 4, &$$);}
+;
+
+term:
+  tVARIABLE {if (!get_variable(yyscanner, $1, 1, &$$)) YYABORT; free($1);}
+| tVARIABLE tSUPNUM {if (!get_variable(yyscanner, $1, $2, &$$)) YYABORT; free($1);}
+| term term {mp_multiply(&$1, &$2, &$$);}
+;
+
+%%