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// Copyright 2009, 2010 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
package runtime
#include "runtime.h"
#include "arch.h"
#include "malloc.h"
#include "go-string.h"
#define charntorune(pv, str, len) __go_get_rune(str, len, pv)
const String runtime_emptystring;
intgo
runtime_findnull(const byte *s)
{
if(s == nil)
return 0;
return __builtin_strlen((const char*) s);
}
static String
gostringsize(intgo l, byte** pmem)
{
String s;
byte *mem;
if(l == 0) {
*pmem = nil;
return runtime_emptystring;
}
// leave room for NUL for C runtime (e.g., callers of getenv)
mem = runtime_mallocgc(l+1, FlagNoPointers, 1, 0);
s.str = mem;
s.len = l;
mem[l] = 0;
*pmem = mem;
return s;
}
String
runtime_gostring(const byte *str)
{
intgo l;
String s;
byte *mem;
l = runtime_findnull(str);
s = gostringsize(l, &mem);
runtime_memmove(mem, str, l);
return s;
}
String
runtime_gostringnocopy(const byte *str)
{
String s;
s.str = str;
s.len = runtime_findnull(str);
return s;
}
enum
{
Runeself = 0x80,
};
func stringiter(s String, k int) (retk int) {
int32 l;
if(k >= s.len) {
// retk=0 is end of iteration
retk = 0;
goto out;
}
l = s.str[k];
if(l < Runeself) {
retk = k+1;
goto out;
}
// multi-char rune
retk = k + charntorune(&l, s.str+k, s.len-k);
out:
}
func stringiter2(s String, k int) (retk int, retv int32) {
if(k >= s.len) {
// retk=0 is end of iteration
retk = 0;
retv = 0;
goto out;
}
retv = s.str[k];
if(retv < Runeself) {
retk = k+1;
goto out;
}
// multi-char rune
retk = k + charntorune(&retv, s.str+k, s.len-k);
out:
}
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