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#include "internal.h"
// new returns a new dynamic string object, initialized from the given c string.
// len defines the length of the c substring that we will copy into our buffer.
// the backing buffer will have capacity cap.
string
str·makecap(const byte *s, vlong len, vlong cap)
{
struct Hdr* h;
h = malloc(sizeof(*h) + cap + 1);
if (s == nil) memset(h, 0, sizeof(*h));
if (h == nil) return nil; // Allocation failed.
h->len = (s == nil) ? 0 : len;
h->cap = cap;
if (cap < h->len) goto cleanup;
if (s != nil && cap > 0) {
memcpy(h->buf, s, h->len);
memset(h->buf + h->len, '\0', h->cap - h->len + 1);
}
return h->buf;
cleanup:
free(h);
panicf("Attempted to create a string with less capacity than length");
return nil;
}
// new returns a new dynamic string object, initialized from the given c string.
// the backing buffer capacity is equivalent to the string length.
string
str·makelen(const byte *s, vlong len)
{
vlong sl = (!s) ? 0 : strlen(s);
if (sl < len) panicf("attempted to take a bigger substring than string length");
vlong cap = (len == 0) ? 1 : len;
return str·makecap(s, len, cap);
}
// new returns a new dynamic string object, initialized from the given c string.
// the backing buffer capacity is equivalent to the string length.
string
str·make(const byte *s)
{
vlong len = (!s) ? 0 : strlen(s);
return str·makelen(s, len);
}
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