return of venti

src/cmd/venti/srv/ifile.c

@@ -0,0 +1,93 @@
+#include "stdinc.h"
+#include "dat.h"
+#include "fns.h"
+
+int
+readifile(IFile *f, char *name)
+{
+	ZBlock *b;
+
+	b = readfile(name);
+	if(b == nil)
+		return -1;
+	f->name = name;
+	f->b = b;
+	f->pos = 0;
+	return 0;
+}
+
+void
+freeifile(IFile *f)
+{
+	freezblock(f->b);
+	f->b = nil;
+	f->pos = 0;
+}
+
+int
+partifile(IFile *f, Part *part, u64int start, u32int size)
+{
+	ZBlock *b;
+
+	b = alloczblock(size, 0, part->blocksize);
+	if(b == nil)
+		return -1;
+	if(readpart(part, start, b->data, size) < 0){
+		seterr(EAdmin, "can't read %s: %r", part->name);
+		freezblock(b);
+		return -1;
+	}
+	f->name = part->name;
+	f->b = b;
+	f->pos = 0;
+	return 0;
+}
+
+/*
+ * return the next non-blank input line,
+ * stripped of leading white space and with # comments eliminated
+ */
+char*
+ifileline(IFile *f)
+{
+	char *s, *e, *t;
+	int c;
+
+	for(;;){
+		s = (char*)&f->b->data[f->pos];
+		e = memchr(s, '\n', f->b->len - f->pos);
+		if(e == nil)
+			return nil;
+		*e++ = '\0';
+		f->pos = e - (char*)f->b->data;
+		t = strchr(s, '#');
+		if(t != nil)
+			*t = '\0';
+		for(; c = *s; s++)
+			if(c != ' ' && c != '\t' && c != '\r')
+				return s;
+	}
+}
+
+int
+ifilename(IFile *f, char *dst)
+{
+	char *s;
+
+	s = ifileline(f);
+	if(s == nil || strlen(s) >= ANameSize)
+		return -1;
+	namecp(dst, s);
+	return 0;
+}
+
+int
+ifileu32int(IFile *f, u32int *r)
+{
+	char *s;
+
+	s = ifileline(f);
+	if(s == nil)
+		return -1;
+	return stru32int(s, r);
+}