| #include "stdio_impl.h" |
| #include <wchar.h> |
| #include <errno.h> |
| #include <limits.h> |
| #include <string.h> |
| |
| struct cookie { |
| wchar_t **bufp; |
| size_t *sizep; |
| size_t pos; |
| wchar_t *buf; |
| size_t len; |
| size_t space; |
| mbstate_t mbs; |
| }; |
| |
| struct wms_FILE { |
| FILE f; |
| struct cookie c; |
| unsigned char buf[1]; |
| }; |
| |
| static off_t wms_seek(FILE *f, off_t off, int whence) |
| { |
| ssize_t base; |
| struct cookie *c = f->cookie; |
| if (whence>2U) { |
| fail: |
| errno = EINVAL; |
| return -1; |
| } |
| base = (size_t [3]){0, c->pos, c->len}[whence]; |
| if (off < -base || off > SSIZE_MAX/4-base) goto fail; |
| memset(&c->mbs, 0, sizeof c->mbs); |
| return c->pos = base+off; |
| } |
| |
| static size_t wms_write(FILE *f, const unsigned char *buf, size_t len) |
| { |
| struct cookie *c = f->cookie; |
| size_t len2; |
| wchar_t *newbuf; |
| if (len + c->pos >= c->space) { |
| len2 = 2*c->space+1 | c->pos+len+1; |
| if (len2 > SSIZE_MAX/4) return 0; |
| newbuf = realloc(c->buf, len2*4); |
| if (!newbuf) return 0; |
| *c->bufp = c->buf = newbuf; |
| memset(c->buf + c->space, 0, 4*(len2 - c->space)); |
| c->space = len2; |
| } |
| |
| len2 = mbsnrtowcs(c->buf+c->pos, (void *)&buf, len, c->space-c->pos, &c->mbs); |
| if (len2 == -1) return 0; |
| c->pos += len2; |
| if (c->pos >= c->len) c->len = c->pos; |
| *c->sizep = c->pos; |
| return len; |
| } |
| |
| static int wms_close(FILE *f) |
| { |
| return 0; |
| } |
| |
| FILE *open_wmemstream(wchar_t **bufp, size_t *sizep) |
| { |
| struct wms_FILE *f; |
| wchar_t *buf; |
| |
| if (!(f=malloc(sizeof *f))) return 0; |
| if (!(buf=malloc(sizeof *buf))) { |
| free(f); |
| return 0; |
| } |
| memset(&f->f, 0, sizeof f->f); |
| memset(&f->c, 0, sizeof f->c); |
| f->f.cookie = &f->c; |
| |
| f->c.bufp = bufp; |
| f->c.sizep = sizep; |
| f->c.pos = f->c.len = f->c.space = *sizep = 0; |
| f->c.buf = *bufp = buf; |
| *buf = 0; |
| |
| f->f.flags = F_NORD; |
| f->f.fd = -1; |
| f->f.buf = f->buf; |
| f->f.buf_size = 0; |
| f->f.lbf = EOF; |
| f->f.write = wms_write; |
| f->f.seek = wms_seek; |
| f->f.close = wms_close; |
| |
| if (!libc.threaded) f->f.lock = -1; |
| |
| return __ofl_add(&f->f); |
| } |