Index: fusl/src/stdio/open_memstream.c |
diff --git a/fusl/src/stdio/open_memstream.c b/fusl/src/stdio/open_memstream.c |
new file mode 100644 |
index 0000000000000000000000000000000000000000..eab024da6cd1766a08f1f54e60aa763730b1a6c8 |
--- /dev/null |
+++ b/fusl/src/stdio/open_memstream.c |
@@ -0,0 +1,90 @@ |
+#include "stdio_impl.h" |
+#include <errno.h> |
+#include <limits.h> |
+#include <string.h> |
+ |
+struct cookie { |
+ char **bufp; |
+ size_t *sizep; |
+ size_t pos; |
+ char *buf; |
+ size_t len; |
+ size_t space; |
+}; |
+ |
+static off_t ms_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-base) goto fail; |
+ return c->pos = base+off; |
+} |
+ |
+static size_t ms_write(FILE *f, const unsigned char *buf, size_t len) |
+{ |
+ struct cookie *c = f->cookie; |
+ size_t len2 = f->wpos - f->wbase; |
+ char *newbuf; |
+ if (len2) { |
+ f->wpos = f->wbase; |
+ if (ms_write(f, f->wbase, len2) < len2) return 0; |
+ } |
+ if (len + c->pos >= c->space) { |
+ len2 = 2*c->space+1 | c->pos+len+1; |
+ newbuf = realloc(c->buf, len2); |
+ if (!newbuf) return 0; |
+ *c->bufp = c->buf = newbuf; |
+ memset(c->buf + c->space, 0, len2 - c->space); |
+ c->space = len2; |
+ } |
+ memcpy(c->buf+c->pos, buf, len); |
+ c->pos += len; |
+ if (c->pos >= c->len) c->len = c->pos; |
+ *c->sizep = c->pos; |
+ return len; |
+} |
+ |
+static int ms_close(FILE *f) |
+{ |
+ return 0; |
+} |
+ |
+FILE *open_memstream(char **bufp, size_t *sizep) |
+{ |
+ FILE *f; |
+ struct cookie *c; |
+ char *buf; |
+ |
+ if (!(f=malloc(sizeof *f + sizeof *c + BUFSIZ))) return 0; |
+ if (!(buf=malloc(sizeof *buf))) { |
+ free(f); |
+ return 0; |
+ } |
+ memset(f, 0, sizeof *f + sizeof *c); |
+ f->cookie = c = (void *)(f+1); |
+ |
+ c->bufp = bufp; |
+ c->sizep = sizep; |
+ c->pos = c->len = c->space = *sizep = 0; |
+ c->buf = *bufp = buf; |
+ *buf = 0; |
+ |
+ f->flags = F_NORD; |
+ f->fd = -1; |
+ f->buf = (void *)(c+1); |
+ f->buf_size = BUFSIZ; |
+ f->lbf = EOF; |
+ f->write = ms_write; |
+ f->seek = ms_seek; |
+ f->close = ms_close; |
+ |
+ if (!libc.threaded) f->lock = -1; |
+ |
+ return __ofl_add(f); |
+} |