lib9: merge create, open, dirread into open.c

Preparation for using opendir.

src/lib9/open.c

@@ -2,11 +2,79 @@
 #include <u.h>
 #define NOPLAN9DEFINES
 #include <sys/file.h>
+#include <unistd.h>
+#include <fcntl.h>
 #include <libc.h>
+#include <sys/stat.h>
+#include <dirent.h>
 #ifndef O_DIRECT
 #define O_DIRECT 0
 #endif
 
+int
+p9create(char *path, int mode, ulong perm)
+{
+	int fd, cexec, umode, rclose, lock, rdwr;
+	struct flock fl;
+
+	rdwr = mode&3;
+	lock = mode&OLOCK;
+	cexec = mode&OCEXEC;
+	rclose = mode&ORCLOSE;
+	mode &= ~(ORCLOSE|OCEXEC|OLOCK);
+
+	/* XXX should get mode mask right? */
+	fd = -1;
+	if(perm&DMDIR){
+		if(mode != OREAD){
+			werrstr("bad mode in directory create");
+			goto out;
+		}
+		if(mkdir(path, perm&0777) < 0)
+			goto out;
+		fd = open(path, O_RDONLY);
+	}else{
+		umode = (mode&3)|O_CREAT|O_TRUNC;
+		mode &= ~(3|OTRUNC);
+		if(mode&ODIRECT){
+			umode |= O_DIRECT;
+			mode &= ~ODIRECT;
+		}
+		if(mode&OEXCL){
+			umode |= O_EXCL;
+			mode &= ~OEXCL;
+		}
+		if(mode&OAPPEND){
+			umode |= O_APPEND;
+			mode &= ~OAPPEND;
+		}
+		if(mode){
+			werrstr("unsupported mode in create");
+			goto out;
+		}
+		fd = open(path, umode, perm);
+	}
+out:
+	if(fd >= 0){
+		if(lock){
+			fl.l_type = (rdwr==OREAD) ? F_RDLCK : F_WRLCK;
+			fl.l_whence = SEEK_SET;
+			fl.l_start = 0;
+			fl.l_len = 0;
+			if(fcntl(fd, F_SETLK, &fl) < 0){
+				close(fd);
+				werrstr("lock: %r");
+				return -1;
+			}
+		}
+		if(cexec)
+			fcntl(fd, F_SETFL, FD_CLOEXEC);
+		if(rclose)
+			remove(path);
+	}
+	return fd;
+}
+
 int
 p9open(char *name, int mode)
 {
@@ -60,3 +128,205 @@ p9open(char *name, int mode)
 	}
 	return fd;
 }
+
+extern int _p9dir(struct stat*, struct stat*, char*, Dir*, char**, char*);
+
+#if defined(__linux__)
+static int
+mygetdents(int fd, struct dirent *buf, int n)
+{
+	off_t off;
+	int nn;
+
+	/* This doesn't match the man page, but it works in Debian with a 2.2 kernel */
+	off = p9seek(fd, 0, 1);
+	nn = getdirentries(fd, (void*)buf, n, &off);
+	return nn;
+}
+#elif defined(__APPLE__)
+static int
+mygetdents(int fd, struct dirent *buf, int n)
+{
+	long off;
+	return getdirentries(fd, (void*)buf, n, &off);
+}
+#elif defined(__FreeBSD__) || defined(__DragonFly__)
+static int
+mygetdents(int fd, struct dirent *buf, int n)
+{
+	off_t off;
+	return getdirentries(fd, (void*)buf, n, &off);
+}
+#elif defined(__sun__) || defined(__NetBSD__) || defined(__OpenBSD__)
+static int
+mygetdents(int fd, struct dirent *buf, int n)
+{
+	return getdents(fd, (void*)buf, n);
+}
+#elif defined(__AIX__)
+static int
+mygetdents(int fd, struct dirent *buf, int n)
+{
+	return getdirent(fd, (void*)buf, n);
+}
+#endif
+
+#if defined(__DragonFly__)
+static inline int d_reclen(struct dirent *de) { return _DIRENT_DIRSIZ(de); }
+#else
+static inline int d_reclen(struct dirent *de) { return de->d_reclen; }
+#endif
+
+static int
+countde(char *p, int n)
+{
+	char *e;
+	int m;
+	struct dirent *de;
+
+	e = p+n;
+	m = 0;
+	while(p < e){
+		de = (struct dirent*)p;
+		if(d_reclen(de) <= 4+2+2+1 || p+d_reclen(de) > e)
+			break;
+		if(de->d_name[0]=='.' && de->d_name[1]==0)
+			de->d_name[0] = 0;
+		else if(de->d_name[0]=='.' && de->d_name[1]=='.' && de->d_name[2]==0)
+			de->d_name[0] = 0;
+		m++;
+		p += d_reclen(de);
+	}
+	return m;
+}
+
+static int
+dirpackage(int fd, char *buf, int n, Dir **dp)
+{
+	int oldwd;
+	char *p, *str, *estr;
+	int i, nstr, m;
+	struct dirent *de;
+	struct stat st, lst;
+	Dir *d;
+
+	n = countde(buf, n);
+	if(n <= 0)
+		return n;
+
+	if((oldwd = open(".", O_RDONLY)) < 0)
+		return -1;
+	if(fchdir(fd) < 0)
+		return -1;
+
+	p = buf;
+	nstr = 0;
+
+	for(i=0; i<n; i++){
+		de = (struct dirent*)p;
+		memset(&lst, 0, sizeof lst);
+		if(de->d_name[0] == 0)
+			/* nothing */ {}
+		else if(lstat(de->d_name, &lst) < 0)
+			de->d_name[0] = 0;
+		else{
+			st = lst;
+			if(S_ISLNK(lst.st_mode))
+				stat(de->d_name, &st);
+			nstr += _p9dir(&lst, &st, de->d_name, nil, nil, nil);
+		}
+		p += d_reclen(de);
+	}
+
+	d = malloc(sizeof(Dir)*n+nstr);
+	if(d == nil){
+		fchdir(oldwd);
+		close(oldwd);
+		return -1;
+	}
+	str = (char*)&d[n];
+	estr = str+nstr;
+
+	p = buf;
+	m = 0;
+	for(i=0; i<n; i++){
+		de = (struct dirent*)p;
+		if(de->d_name[0] != 0 && lstat(de->d_name, &lst) >= 0){
+			st = lst;
+			if((lst.st_mode&S_IFMT) == S_IFLNK)
+				stat(de->d_name, &st);
+			_p9dir(&lst, &st, de->d_name, &d[m++], &str, estr);
+		}
+		p += d_reclen(de);
+	}
+
+	fchdir(oldwd);
+	close(oldwd);
+	*dp = d;
+	return m;
+}
+
+long
+dirread(int fd, Dir **dp)
+{
+	char *buf;
+	struct stat st;
+	int n;
+
+	*dp = 0;
+
+	if(fstat(fd, &st) < 0)
+		return -1;
+
+	if(st.st_blksize < 8192)
+		st.st_blksize = 8192;
+
+	buf = malloc(st.st_blksize);
+	if(buf == nil)
+		return -1;
+
+	n = mygetdents(fd, (void*)buf, st.st_blksize);
+	if(n < 0){
+		free(buf);
+		return -1;
+	}
+	n = dirpackage(fd, buf, n, dp);
+	free(buf);
+	return n;
+}
+
+
+long
+dirreadall(int fd, Dir **d)
+{
+	uchar *buf, *nbuf;
+	long n, ts;
+	struct stat st;
+
+	if(fstat(fd, &st) < 0)
+		return -1;
+
+	if(st.st_blksize < 8192)
+		st.st_blksize = 8192;
+
+	buf = nil;
+	ts = 0;
+	for(;;){
+		nbuf = realloc(buf, ts+st.st_blksize);
+		if(nbuf == nil){
+			free(buf);
+			return -1;
+		}
+		buf = nbuf;
+		n = mygetdents(fd, (void*)(buf+ts), st.st_blksize);
+		if(n <= 0)
+			break;
+		ts += n;
+	}
+	if(ts >= 0)
+		ts = dirpackage(fd, (char*)buf, ts, d);
+	free(buf);
+	if(ts == 0 && n < 0)
+		return -1;
+	return ts;
+}