Re-implement some operations from string.py in C, for speed.

diff --git a/Modules/stropmodule.c b/Modules/stropmodule.c
new file mode 100644 (file)
index 0000000..cc2e26a
--- /dev/null
+++ b/Modules/stropmodule.c
@@ -0,0 +1,201 @@
+/***********************************************************
+Copyright 1991, 1992 by Stichting Mathematisch Centrum, Amsterdam, The
+Netherlands.
+
+                        All Rights Reserved
+
+Permission to use, copy, modify, and distribute this software and its 
+documentation for any purpose and without fee is hereby granted, 
+provided that the above copyright notice appear in all copies and that
+both that copyright notice and this permission notice appear in 
+supporting documentation, and that the names of Stichting Mathematisch
+Centrum or CWI not be used in advertising or publicity pertaining to
+distribution of the software without specific, written prior permission.
+
+STICHTING MATHEMATISCH CENTRUM DISCLAIMS ALL WARRANTIES WITH REGARD TO
+THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND
+FITNESS, IN NO EVENT SHALL STICHTING MATHEMATISCH CENTRUM BE LIABLE
+FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
+OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+
+******************************************************************/
+
+/* strop module */
+
+#include "allobjects.h"
+#include "modsupport.h"
+
+
+static object *
+strop_split(self, args)
+       object *self; /* Not used */
+       object *args;
+{
+       int len, i, j;
+       char *s;
+       char c;
+       object *list, *item;
+
+       if (!getargs(args, "s#", &s, &len))
+               return NULL;
+       list = newlistobject(0);
+       if (list == NULL)
+               return NULL;
+
+       i = 0;
+       while (i < len) {
+               while (i < len &&
+                      ((c = s[i]) == ' ' || c == '\t' || c == '\n')) {
+                       i = i+1;
+               }
+               j = i;
+               while (i < len &&
+                      !((c = s[i]) == ' ' || c == '\t' || c == '\n')) {
+                       i = i+1;
+               }
+               if (j < i) {
+                       item = newsizedstringobject(s+j, (int)(i-j));
+                       if (item == NULL || addlistitem(list, item) < 0) {
+                               DECREF(list);
+                               return NULL;
+                       }
+               }
+       }
+
+       return list;
+}
+
+
+static object *
+strop_splitfields(self, args)
+       object *self; /* Not used */
+       object *args;
+{
+       int len, n, i, j;
+       char *s, *sub;
+       char c;
+       object *list, *item;
+
+       if (!getargs(args, "(s#s#)", &s, &len, &sub, &n))
+               return NULL;
+       if (n == 0) {
+               err_setstr(ValueError, "empty separator");
+               return NULL;
+       }
+
+       list = newlistobject(0);
+       if (list == NULL)
+               return NULL;
+
+       i = j = 0;
+       while (i+n <= len) {
+               if (s[i] == sub[0] && (n == 1 || strncmp(s+i, sub, n) == 0)) {
+                       item = newsizedstringobject(s+j, (int)(i-j));
+                       if (item == NULL || addlistitem(list, item) < 0) {
+                               DECREF(list);
+                               return NULL;
+                       }
+                       i = j = i + n;
+               }
+               else
+                       i++;
+       }
+       item = newsizedstringobject(s+j, (int)(len-j));
+       if (item == NULL || addlistitem(list, item) < 0) {
+               DECREF(list);
+               return NULL;
+       }
+
+       return list;
+}
+
+
+static object *
+strop_index(self, args)
+       object *self; /* Not used */
+       object *args;
+{
+       char *s, *sub;
+       int len, n, i;
+
+       if (getargs(args, "(s#s#i)", &s, &len, &sub, &n, &i)) {
+               if (i < 0 || i+n > len) {
+                       err_setstr(ValueError, "start offset out of range");
+                       return NULL;
+               }
+       }
+       else {
+               err_clear();
+               if (!getargs(args, "(s#s#)", &s, &len, &sub, &n))
+                       return NULL;
+               i = 0;
+       }
+
+       if (n == 0)
+               return newintobject((long)i);
+
+       len -= n;
+       for (; i <= len; i++) {
+               if (s[i] == sub[0]) {
+                       if (n == 1 || strncmp(s+i, sub, n) == 0)
+                               return newintobject((long)i);
+               }
+       }
+
+       err_setstr(ValueError, "substring not found");
+       return NULL;
+}
+
+
+static object *
+strop_strip(self, args)
+       object *self; /* Not used */
+       object *args;
+{
+       char *s;
+       int len, i, j;
+       char c;
+
+       if (!getargs(args, "s#", &s, &len))
+               return NULL;
+
+       i = 0;
+       while (i < len && ((c = s[i]) == ' ' || c == '\t' || c == '\n')) {
+               i++;
+       }
+
+       j = len;
+       do {
+               j--;
+       } while (j >= i &&  ((c = s[j]) == ' ' || c == '\t' || c == '\n'));
+       j++;
+
+       if (i == 0 && j == len) {
+               INCREF(args);
+               return args;
+       }
+       else
+               return newsizedstringobject(s+i, j-i);
+}
+
+
+/* List of functions defined in the module */
+
+static struct methodlist strop_methods[] = {
+       {"index",       strop_index},
+       {"split",       strop_split},
+       {"splitfields", strop_splitfields},
+       {"strip",       strop_strip},
+       {NULL,          NULL}   /* sentinel */
+};
+
+
+/* Initialization function for the module (*must* be called initstrop) */
+
+void
+initstrop()
+{
+       initmodule("strop", strop_methods);
+}