ref: e19308ee166dd085f7773621471a5fc589af45d4
dir: /sys/src/libString/s_read.c/
#include <u.h> #include <libc.h> #include <bio.h> #include "String.h" enum { Minread= 256, }; /* Append up to 'len' input bytes to the string 'to'. * * Returns the number of characters read. */ extern int s_read(Biobuf *fp, String *to, int len) { int rv; int n; if(to->ref > 1) sysfatal("can't s_read a shared string"); for(rv = 0; rv < len; rv += n){ n = to->end - to->ptr; if(n < Minread){ s_grow(to, Minread); n = to->end - to->ptr; } if(n > len - rv) n = len - rv; n = Bread(fp, to->ptr, n); if(n <= 0) break; to->ptr += n; } s_terminate(to); return rv; }