zig/lib/std/valgrind/memcheck.zig
Frank Denis 4930094e62 valgrind.memcheck: fix makeMem*()
The `makeMem*()` functions crashed under valgrind in Debug and
ReleaseSafe modes.

The reason being that `doMemCheckClientRequestExpr()` returns `0`
when not running under Valgrind, and `maxInt(usize)` when running
under Valgrind.

Thus, `@as(i1, @intCast(maxInt(usize)))` always fails and these
functions crashed before returning.

That being said, what these functions used to return was quite
unexpected: `0` on error and `-1` on success (=running under valgrind).
That doesn't match any Zig nor C conventions.

But that return value doesn't seem to be very useful. Either we are
running under Valgrind or we are not. There's no point in checking this
for every single call. Applications are likely to always discard it.

So, just return a `void` instead.

Also avoid function comments that start with `Similarly, ...` because
that doesn't refer to anything in the context of autodoc or in IDEs.
2023-10-03 02:51:01 -07:00

219 lines
7.5 KiB
Zig

const std = @import("../std.zig");
const testing = std.testing;
const valgrind = std.valgrind;
pub const MemCheckClientRequest = enum(usize) {
MakeMemNoAccess = valgrind.ToolBase("MC".*),
MakeMemUndefined,
MakeMemDefined,
Discard,
CheckMemIsAddressable,
CheckMemIsDefined,
DoLeakCheck,
CountLeaks,
GetVbits,
SetVbits,
CreateBlock,
MakeMemDefinedIfAddressable,
CountLeakBlocks,
EnableAddrErrorReportingInRange,
DisableAddrErrorReportingInRange,
};
fn doMemCheckClientRequestExpr(default: usize, request: MemCheckClientRequest, a1: usize, a2: usize, a3: usize, a4: usize, a5: usize) usize {
return valgrind.doClientRequest(default, @as(usize, @intCast(@intFromEnum(request))), a1, a2, a3, a4, a5);
}
fn doMemCheckClientRequestStmt(request: MemCheckClientRequest, a1: usize, a2: usize, a3: usize, a4: usize, a5: usize) void {
_ = doMemCheckClientRequestExpr(0, request, a1, a2, a3, a4, a5);
}
/// Mark memory at qzz.ptr as unaddressable for qzz.len bytes.
pub fn makeMemNoAccess(qzz: []u8) void {
_ = doMemCheckClientRequestExpr(0, // default return
.MakeMemNoAccess, @intFromPtr(qzz.ptr), qzz.len, 0, 0, 0);
}
/// Mark memory at qzz.ptr as addressable but undefined for qzz.len bytes.
pub fn makeMemUndefined(qzz: []u8) void {
_ = doMemCheckClientRequestExpr(0, // default return
.MakeMemUndefined, @intFromPtr(qzz.ptr), qzz.len, 0, 0, 0);
}
/// Mark memory at qzz.ptr as addressable and defined or qzz.len bytes.
pub fn makeMemDefined(qzz: []u8) void {
_ = doMemCheckClientRequestExpr(0, // default return
.MakeMemDefined, @intFromPtr(qzz.ptr), qzz.len, 0, 0, 0);
}
/// Similar to makeMemDefined except that addressability is
/// not altered: bytes which are addressable are marked as defined,
/// but those which are not addressable are left unchanged.
pub fn makeMemDefinedIfAddressable(qzz: []u8) void {
_ = doMemCheckClientRequestExpr(0, // default return
.MakeMemDefinedIfAddressable, @intFromPtr(qzz.ptr), qzz.len, 0, 0, 0);
}
/// Create a block-description handle. The description is an ascii
/// string which is included in any messages pertaining to addresses
/// within the specified memory range. Has no other effect on the
/// properties of the memory range.
pub fn createBlock(qzz: []u8, desc: [*]u8) usize {
return doMemCheckClientRequestExpr(0, // default return
.CreateBlock, @intFromPtr(qzz.ptr), qzz.len, @intFromPtr(desc), 0, 0);
}
/// Discard a block-description-handle. Returns 1 for an
/// invalid handle, 0 for a valid handle.
pub fn discard(blkindex: usize) bool {
return doMemCheckClientRequestExpr(0, // default return
.Discard, 0, blkindex, 0, 0, 0) != 0;
}
/// Check that memory at qzz.ptr is addressable for qzz.len bytes.
/// If suitable addressability is not established, Valgrind prints an
/// error message and returns the address of the first offending byte.
/// Otherwise it returns zero.
pub fn checkMemIsAddressable(qzz: []u8) usize {
return doMemCheckClientRequestExpr(0, .CheckMemIsAddressable, @intFromPtr(qzz.ptr), qzz.len, 0, 0, 0);
}
/// Check that memory at qzz.ptr is addressable and defined for
/// qzz.len bytes. If suitable addressability and definedness are not
/// established, Valgrind prints an error message and returns the
/// address of the first offending byte. Otherwise it returns zero.
pub fn checkMemIsDefined(qzz: []u8) usize {
return doMemCheckClientRequestExpr(0, .CheckMemIsDefined, @intFromPtr(qzz.ptr), qzz.len, 0, 0, 0);
}
/// Do a full memory leak check (like --leak-check=full) mid-execution.
pub fn doLeakCheck() void {
doMemCheckClientRequestStmt(.DO_LEAK_CHECK, 0, 0, 0, 0, 0);
}
/// Same as doLeakCheck() but only showing the entries for
/// which there was an increase in leaked bytes or leaked nr of blocks
/// since the previous leak search.
pub fn doAddedLeakCheck() void {
doMemCheckClientRequestStmt(.DO_LEAK_CHECK, 0, 1, 0, 0, 0);
}
/// Same as doAddedLeakCheck() but showing entries with
/// increased or decreased leaked bytes/blocks since previous leak
/// search.
pub fn doChangedLeakCheck() void {
doMemCheckClientRequestStmt(.DO_LEAK_CHECK, 0, 2, 0, 0, 0);
}
/// Do a summary memory leak check (like --leak-check=summary) mid-execution.
pub fn doQuickLeakCheck() void {
doMemCheckClientRequestStmt(.DO_LEAK_CHECK, 1, 0, 0, 0, 0);
}
/// Return number of leaked, dubious, reachable and suppressed bytes found by
/// all previous leak checks.
const CountResult = struct {
leaked: usize,
dubious: usize,
reachable: usize,
suppressed: usize,
};
pub fn countLeaks() CountResult {
var res: CountResult = .{
.leaked = 0,
.dubious = 0,
.reachable = 0,
.suppressed = 0,
};
doMemCheckClientRequestStmt(
.CountLeaks,
@intFromPtr(&res.leaked),
@intFromPtr(&res.dubious),
@intFromPtr(&res.reachable),
@intFromPtr(&res.suppressed),
0,
);
return res;
}
test "countLeaks" {
try testing.expectEqual(
@as(CountResult, .{
.leaked = 0,
.dubious = 0,
.reachable = 0,
.suppressed = 0,
}),
countLeaks(),
);
}
pub fn countLeakBlocks() CountResult {
var res: CountResult = .{
.leaked = 0,
.dubious = 0,
.reachable = 0,
.suppressed = 0,
};
doMemCheckClientRequestStmt(
.CountLeakBlocks,
@intFromPtr(&res.leaked),
@intFromPtr(&res.dubious),
@intFromPtr(&res.reachable),
@intFromPtr(&res.suppressed),
0,
);
return res;
}
test "countLeakBlocks" {
try testing.expectEqual(
@as(CountResult, .{
.leaked = 0,
.dubious = 0,
.reachable = 0,
.suppressed = 0,
}),
countLeakBlocks(),
);
}
/// Get the validity data for addresses zza and copy it
/// into the provided zzvbits array. Return values:
/// 0 if not running on valgrind
/// 1 success
/// 2 [previously indicated unaligned arrays; these are now allowed]
/// 3 if any parts of zzsrc/zzvbits are not addressable.
/// The metadata is not copied in cases 0, 2 or 3 so it should be
/// impossible to segfault your system by using this call.
pub fn getVbits(zza: []u8, zzvbits: []u8) u2 {
std.debug.assert(zzvbits.len >= zza.len / 8);
return @as(u2, @intCast(doMemCheckClientRequestExpr(0, .GetVbits, @intFromPtr(zza.ptr), @intFromPtr(zzvbits), zza.len, 0, 0)));
}
/// Set the validity data for addresses zza, copying it
/// from the provided zzvbits array. Return values:
/// 0 if not running on valgrind
/// 1 success
/// 2 [previously indicated unaligned arrays; these are now allowed]
/// 3 if any parts of zza/zzvbits are not addressable.
/// The metadata is not copied in cases 0, 2 or 3 so it should be
/// impossible to segfault your system by using this call.
pub fn setVbits(zzvbits: []u8, zza: []u8) u2 {
std.debug.assert(zzvbits.len >= zza.len / 8);
return @as(u2, @intCast(doMemCheckClientRequestExpr(0, .SetVbits, @intFromPtr(zza.ptr), @intFromPtr(zzvbits), zza.len, 0, 0)));
}
/// Disable and re-enable reporting of addressing errors in the
/// specified address range.
pub fn disableAddrErrorReportingInRange(qzz: []u8) usize {
return doMemCheckClientRequestExpr(0, // default return
.DisableAddrErrorReportingInRange, @intFromPtr(qzz.ptr), qzz.len, 0, 0, 0);
}
pub fn enableAddrErrorReportingInRange(qzz: []u8) usize {
return doMemCheckClientRequestExpr(0, // default return
.EnableAddrErrorReportingInRange, @intFromPtr(qzz.ptr), qzz.len, 0, 0, 0);
}