#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;}