authorgravatar for andrew@ziglang.orgAndrew Kelley <andrew@ziglang.org> 2020-03-11 16:14:12-04:00
committergravatar for andrew@ziglang.orgAndrew Kelley <andrew@ziglang.org> 2020-03-11 16:14:12-04:00
log6892865ba72ea220a12a8238ce78aedab1237cce
treeec60bbfbd034db797cb0ae9a19e52e2d2af8f9cb
parent04626c176b328f7ae937b0828f14f4b4be62b733
signaturelock-open Commit is signed but in an unrecognized format.

FixedBufferStream: match file semantics more by clamping pos


1 files changed, 8 insertions(+), 8 deletions(-)

lib/std/io/fixed_buffer_stream.zig+8-8
......@@ -76,21 +76,22 @@ pub fn FixedBufferStream(comptime Buffer: type) type {
7676 }
7777
7878 pub fn seekTo(self: *Self, pos: u64) SeekError!void {
79 const usize_pos = std.math.cast(usize, pos) catch std.math.maxInt(usize);
80 self.pos = usize_pos;
79 self.pos = if (std.math.cast(usize, pos)) |x| x else |_| self.buffer.len;
8180 }
8281
8382 pub fn seekBy(self: *Self, amt: i64) SeekError!void {
8483 if (amt < 0) {
85 const abs_amt = std.math.cast(usize, -amt) catch std.math.maxInt(usize);
86 if (abs_amt > self.pos) {
84 const abs_amt = std.math.absCast(amt);
85 const abs_amt_usize = std.math.cast(usize, abs_amt) catch std.math.maxInt(usize);
86 if (abs_amt_usize > self.pos) {
8787 self.pos = 0;
8888 } else {
89 self.pos -= abs_amt;
89 self.pos -= abs_amt_usize;
9090 }
9191 } else {
92 const usize_amt = std.math.cast(usize, amt) catch std.math.maxInt(usize);
93 self.pos = std.math.add(usize, self.pos, usize_amt) catch std.math.maxInt(usize);
92 const amt_usize = std.math.cast(usize, amt) catch std.math.maxInt(usize);
93 const new_pos = std.math.add(usize, self.pos, amt_usize) catch std.math.maxInt(usize);
94 self.pos = std.math.min(self.buffer.len, new_pos);
9495 }
9596 }
9697
......@@ -102,7 +103,6 @@ pub fn FixedBufferStream(comptime Buffer: type) type {
102103 return self.pos;
103104 }
104105
105 /// Asserts that the seek pos is within the buffer range.
106106 pub fn getWritten(self: Self) []const u8 {
107107 return self.buffer[0..self.pos];
108108 }