[gcalctool/gcalctool-newui2] Support SI units

[Robert Ancell <rancell src gnome org>]

commit ac417b6af9f2f408c50df66f19b7efa3b807804a
Author: Robert Ancell <robert ancell gmail com>
Date:   Thu Jul 2 14:40:02 2009 +1000

    Support SI units

 src/mp-convert.c        |   40 ++++++++++++++++++++++++++++++++--------
 src/mp-equation-lexer.l |    3 ++-
 2 files changed, 34 insertions(+), 9 deletions(-)
---
diff --git a/src/mp-convert.c b/src/mp-convert.c
index e693445..1505f5c 100644
--- a/src/mp-convert.c
+++ b/src/mp-convert.c
@@ -594,13 +594,17 @@ char_val(char chr, int base)
 void
 mp_set_from_string(const char *str, MPNumber *z)
 {
-    int i, base, negate = 0;
+    int i, base, negate = 0, multiplier = 0;
     const char *c, *end;
+    gboolean has_fraction = FALSE;
+    
     const char *base_suffixes[] = {"â??", "â??", "â??â??", NULL};
-    int base_values[] = {2, 8, 16, 10};
-    const char *fractions[] = {"½", "â??", "â??", "¼", "¾", "â??", "â??", "â??", "â??", "â??", "â??", "â??", "â??", "â??", "â??", NULL};
-    int numerators[]        = { 1,   1,   2,   1,   3,   1,   2,   3,   4,   1,   5,   1,   3,   5,   7};
-    int denominators[]      = { 2,   3,   3,   4,   4,   5,   5,   5,   5,   6,   6,   8,   8,   8,   8};
+    int base_values[]           = {2, 8, 16, 10};
+    const char *fractions[]     = {"½", "â??", "â??", "¼", "¾", "â??", "â??", "â??", "â??", "â??", "â??", "â??", "â??", "â??", "â??", NULL};
+    int numerators[]            = { 1,   1,   2,   1,   3,   1,   2,   3,   4,   1,   5,   1,   3,   5,   7};
+    int denominators[]          = { 2,   3,   3,   4,   4,   5,   5,   5,   5,   6,   6,   8,   8,   8,   8};
+    const char *si_suffixes[]   = {"T", "G", "M", "k", "d", "c", "m", "u", "µ", "n", "p", "f", NULL};
+    int si_multipliers[]        = { 12,   9,   6,   3,  -1,  -2,  -3,  -6,  -6,  -9, -12, -15};
     
     /* Find the base */
     end = str;
@@ -644,12 +648,25 @@ mp_set_from_string(const char *str, MPNumber *z)
         mp_set_from_fraction(numerators[i], denominators[i], &fraction);
         mp_add(z, &fraction, z);
     }
+    
+    if (*c == '.') {
+        has_fraction = TRUE;
+        c++;
+    } else {
+        for (i = 0; si_suffixes[i] != NULL; i++) {
+            if (strncmp(c, si_suffixes[i], strlen(si_suffixes[i])) == 0)
+                break;
+        }
+        if (si_suffixes[i] != NULL) {
+            has_fraction = TRUE;
+            multiplier = si_multipliers[i];
+            c += strlen(si_suffixes[i]);
+        }
+    }
    
     /* Convert fractional part */
-    if (*c == '.') {
+    if (has_fraction) {
         MPNumber numerator, denominator;
-       
-        c++;
 
         mp_set_from_integer(0, &numerator);
         mp_set_from_integer(1, &denominator);
@@ -666,6 +683,13 @@ mp_set_from_string(const char *str, MPNumber *z)
     if (c != end) {
        // FIXME: Error decoding
     }
+    
+    if (multiplier != 0) {
+        MPNumber t;
+        mp_set_from_integer(10, &t);
+        mp_pwr_integer(&t, multiplier, &t);
+        mp_multiply(z, &t, z);
+    }
  
     if (negate == 1)
         mp_invert_sign(z, z);
diff --git a/src/mp-equation-lexer.l b/src/mp-equation-lexer.l
index 9a7be18..2855cac 100644
--- a/src/mp-equation-lexer.l
+++ b/src/mp-equation-lexer.l
@@ -77,12 +77,13 @@ OCT_SUFFIX   "â??"
 DEC          [0-9]
 HEX          [0-9]|[A-F]|[a-f]
 HEX_SUFFIX   "â??â??"
+SI_SUFFIX    "T"|"G"|"M"|"k"|"d"|"c"|"m"|"u"|"µ"|"n"|"p"|"f"
 SUPER_DIGITS "�"|"¹"|"²"|"³"|"�"|"�"|"�"|"�"|"�"|"�"
 SUB_DIGITS   "â??"|"â??"|"â??"|"â??"|"â??"|"â??"|"â??"|"â??"|"â??"|"â??"
 FRACTION     "½"|"â??"|"â??"|"¼"|"¾"|"â??"|"â??"|"â??"|"â??"|"â??"|"â??"|"â??"|"â??"|"â??"|"â??"
 
 HEX_NUM {HEX}+{HEX_SUFFIX}|{HEX}*{DECIMAL}{HEX}+{HEX_SUFFIX}
-DEC_NUM {DEC}+|{DEC}*{DECIMAL}{DEC}+|{FRACTION}|{DEC}{FRACTION}
+DEC_NUM {DEC}+|{DEC}+{SI_SUFFIX}|{DEC}*{DECIMAL}{DEC}+|{DEC}*{SI_SUFFIX}{DEC}+|{FRACTION}|{DEC}{FRACTION}
 OCT_NUM {OCT}+{OCT_SUFFIX}|{OCT}*{DECIMAL}{OCT}+{OCT_SUFFIX}
 BIN_NUM {BIN}+{BIN_SUFFIX}|{BIN}*{DECIMAL}{BIN}+{BIN_SUFFIX}
 SUP_NUM {SUPER_DIGITS}+