1 files changed, 37 insertions, 0 deletions
diff --git a/libc-top-half/musl/src/internal/shgetc.c b/libc-top-half/musl/src/internal/shgetc.c
new file mode 100644
index 0000000..7455d2f
--- /dev/null
+++ b/libc-top-half/musl/src/internal/shgetc.c
@@ -0,0 +1,37 @@
+#include "shgetc.h"
+
+/* The shcnt field stores the number of bytes read so far, offset by
+ * the value of buf-rpos at the last function call (__shlim or __shgetc),
+ * so that between calls the inline shcnt macro can add rpos-buf to get
+ * the actual count. */
+
+void __shlim(FILE *f, off_t lim)
+{
+	f->shlim = lim;
+	f->shcnt = f->buf - f->rpos;
+	/* If lim is nonzero, rend must be a valid pointer. */
+	if (lim && f->rend - f->rpos > lim)
+		f->shend = f->rpos + lim;
+	else
+		f->shend = f->rend;
+}
+
+int __shgetc(FILE *f)
+{
+	int c;
+	off_t cnt = shcnt(f);
+	if (f->shlim && cnt >= f->shlim || (c=__uflow(f)) < 0) {
+		f->shcnt = f->buf - f->rpos + cnt;
+		f->shend = f->rpos;
+		f->shlim = -1;
+		return EOF;
+	}
+	cnt++;
+	if (f->shlim && f->rend - f->rpos > f->shlim - cnt)
+		f->shend = f->rpos + (f->shlim - cnt);
+	else
+		f->shend = f->rend;
+	f->shcnt = f->buf - f->rpos + cnt;
+	if (f->rpos <= f->buf) f->rpos[-1] = c;
+	return c;
+}