1 files changed, 84 insertions, 0 deletions
diff --git a/libinterp/readmod.c b/libinterp/readmod.c
new file mode 100644
index 00000000..eebc9ba5
--- /dev/null
+++ b/libinterp/readmod.c
@@ -0,0 +1,84 @@
+#include "lib9.h"
+#include "isa.h"
+#include "interp.h"
+#include "kernel.h"
+#include "dynld.h"
+
+Module*
+readmod(char *path, Module *m, int sync)
+{
+	Dir *d;
+	int fd, n, dynld;
+	uchar *code;
+	Module *ans;
+	ulong length;
+
+	if(path[0] == '$') {
+		if(m == nil)
+			kwerrstr("module not built-in");
+		return m;
+	}
+
+	ans = nil;
+	code = nil;
+	length = 0;
+	dynld = 0;
+
+	if(sync)
+		release();
+
+	d = nil;
+	fd = kopen(path, OREAD);
+	if(fd < 0)
+		goto done;
+
+	if((d = kdirfstat(fd)) == nil)
+		goto done;
+
+	if(m != nil) {
+		if(d->dev == m->dev && d->type == m->dtype &&
+		   d->mtime == m->mtime &&
+		   d->qid.type == m->qid.type && d->qid.path == m->qid.path && d->qid.vers == m->qid.vers) {
+			ans = m;
+			goto done;
+		}
+	}
+
+	if(d->length < 0 || d->length >= 8*1024*1024){
+		kwerrstr("implausible length");
+		goto done;
+	}
+	if((d->mode&0111) && dynldable(fd)){
+		dynld = 1;
+		goto done1;
+	}
+	length = d->length;
+	code = mallocz(length, 0);
+	if(code == nil)
+		goto done;
+
+	n = kread(fd, code, length);
+	if(n != length) {
+		free(code);
+		code = nil;
+	}
+done:
+	if(fd >= 0)
+		kclose(fd);
+done1:
+	if(sync)
+		acquire();
+	if(m != nil && ans == nil)
+		unload(m);
+	if(code != nil) {
+		ans = parsemod(path, code, length, d);
+		free(code);
+	}
+	else if(dynld){
+		kseek(fd, 0, 0);
+		ans = newdyncode(fd, path, d);
+		kclose(fd);
+	}
+	free(d);
+	return ans;
+}