Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Add BufferOverflowMode for FixedAppender #12

Merged
merged 1 commit into from
Apr 2, 2024
Merged

Add BufferOverflowMode for FixedAppender #12

Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
61 changes: 60 additions & 1 deletion source/vibe/container/internal/appender.d
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -208,7 +208,7 @@ unittest {
}


struct FixedAppender(ArrayType : E[], size_t NELEM, E) {
struct FixedAppender(ArrayType : E[], size_t NELEM, BufferOverflowMode OM = BufferOverflowMode.none, E) {
alias ElemType = Unqual!E;
private {
ElemType[NELEM] m_data;
Expand All @@ -222,6 +222,14 @@ struct FixedAppender(ArrayType : E[], size_t NELEM, E) {

void put(E el)
{
static if (OM == BufferOverflowMode.exception) {
if (m_fill >= m_data.length)
throw new Exception("Writing past end of FixedAppender");
} else static if (OM == BufferOverflowMode.ignore) {
if (m_fill >= m_data.length)
return;
}

m_data[m_fill++] = el;
}

Expand Down Expand Up @@ -253,6 +261,18 @@ struct FixedAppender(ArrayType : E[], size_t NELEM, E) {

void put(ArrayType arr)
{
static if (OM == BufferOverflowMode.exception) {
if (m_fill + arr.length > m_data.length) {
put(arr[0 .. m_data.length - m_fill]);
throw new Exception("Writing past end of FixedAppender");
}
} else static if (OM == BufferOverflowMode.ignore) {
if (m_fill + arr.length > m_data.length) {
put(arr[0 .. m_data.length - m_fill]);
return;
}
}

m_data[m_fill .. m_fill+arr.length] = arr[];
m_fill += arr.length;
}
Expand All @@ -271,3 +291,42 @@ unittest {
app.put("ar");
assert(app.data == "foobar");
}

unittest {
import std.exception : assertThrown;
import std.format : formattedWrite;

FixedAppender!(string, 8) fa1;
fa1.formattedWrite("foo: %s", 42);
assert(fa1.data == "foo: 42");

FixedAppender!(string, 6, BufferOverflowMode.exception) fa2;
fa2.formattedWrite("foo: %s", 1);
assert(fa2.data == "foo: 1");
fa2.clear();
assertThrown(fa2.formattedWrite("foo: %s", 42));
assert(fa2.data == "foo: 4");
assertThrown(fa2.put('\a'));
assertThrown(fa2.put("bc"));
assert(fa2.data == "foo: 4");

FixedAppender!(string, 6, BufferOverflowMode.ignore) fa3;
fa3.formattedWrite("foo: %s", 1);
assert(fa3.data == "foo: 1");
fa3.clear();
fa3.formattedWrite("foo: %s", 42);
assert(fa2.data == "foo: 4");
fa3.put('\a');
fa3.put("bc");
assert(fa3.data == "foo: 4");
}


/** Determines how to handle buffer overflows in `FixedAppender`.
*/
enum BufferOverflowMode {
none, /// Results in an ArrayBoundsError and terminates the application
exception, /// Throws an exception
ignore /// Skips any extraneous bytes written
}

Loading