1 files changed, 158 insertions, 0 deletions
diff --git a/third_party/rust/minidump-writer/tests/task_dumper.rs b/third_party/rust/minidump-writer/tests/task_dumper.rs
new file mode 100644
index 0000000000..1411acc34a
--- /dev/null
+++ b/third_party/rust/minidump-writer/tests/task_dumper.rs
@@ -0,0 +1,158 @@
+//! All of these tests are specific to the MacOS task dumper
+#![cfg(target_os = "macos")]
+
+use minidump_writer::{mach::LoadCommand, task_dumper::TaskDumper};
+use std::fmt::Write;
+
+fn call_otool(args: &[&str]) -> String {
+    let mut cmd = std::process::Command::new("otool");
+    cmd.args(args);
+
+    let exe_path = std::env::current_exe().expect("unable to retrieve test executable path");
+    cmd.arg(exe_path);
+
+    let output = cmd.output().expect("failed to spawn otool");
+
+    assert!(output.status.success());
+
+    String::from_utf8(output.stdout).expect("stdout was invalid utf-8")
+}
+
+/// Validates we can iterate the load commands for all of the images in the task
+#[test]
+fn iterates_load_commands() {
+    let lc_str = call_otool(&["-l"]);
+
+    let mut expected = String::new();
+    let mut lc_index = 0;
+
+    expected.push('\n');
+
+    while let Some(nlc) = lc_str[lc_index..].find("Load command ") {
+        lc_index += nlc;
+
+        let block = match lc_str[lc_index + 13..].find("Load command ") {
+            Some(ind) => &lc_str[lc_index + 13..lc_index + 13 + ind],
+            None => &lc_str[lc_index..],
+        };
+
+        // otool prints the load command index for each command, but we only
+        // handle the small subset of the available load commands we care about
+        // so just ignore that
+        let block = &block[block.find('\n').unwrap() + 1..];
+
+        // otool also prints all the sections for LC_SEGMENT_* commands, but
+        // we don't care about those, so ignore them
+        let block = match block.find("Section") {
+            Some(ind) => &block[..ind],
+            None => block,
+        };
+
+        lc_index += 13;
+
+        let cmd = block
+            .find("cmd ")
+            .expect("load commnd didn't specify cmd kind");
+        let cmd_end = block[cmd..]
+            .find('\n')
+            .expect("load cmd didn't end with newline");
+        if matches!(
+            &block[cmd + 4..cmd + cmd_end],
+            "LC_SEGMENT_64" | "LC_UUID" | "LC_ID_DYLIB" | "LC_LOAD_DYLINKER"
+        ) {
+            expected.push_str(block);
+        }
+    }
+
+    let task_dumper = TaskDumper::new(
+        // SAFETY: syscall
+        unsafe { mach2::traps::mach_task_self() },
+    );
+
+    let mut actual = String::new();
+
+    // Unfortunately, Apple decided to move dynamic libs into a shared cache,
+    // removing them from the file system completely, and unless I'm missing it
+    // there is no way to get the load commands for the dylibs since otool
+    // only understands file paths? So we just get the load commands for the main
+    // executable instead, this means that we miss the `LC_ID_DYLIB` commands
+    // since they only apply to dylibs, but this test is more that we can
+    // correctly iterate through the load commands themselves, so this _should_
+    // be fine...
+    let exe_img = task_dumper
+        .read_executable_image()
+        .expect("failed to read executable image");
+
+    {
+        let lcmds = task_dumper
+            .read_load_commands(&exe_img)
+            .expect("failed to read load commands");
+
+        for lc in lcmds.iter() {
+            match lc {
+                LoadCommand::Segment(seg) => {
+                    let segname = std::str::from_utf8(&seg.segment_name).unwrap();
+                    let segname = &segname[..segname.find('\0').unwrap()];
+                    write!(
+                        &mut actual,
+                        "
+      cmd LC_SEGMENT_64
+  cmdsize {}
+  segname {}
+   vmaddr 0x{:016x}
+   vmsize 0x{:016x}
+  fileoff {}
+ filesize {}
+  maxprot 0x{:08x}
+ initprot 0x{:08x}
+   nsects {}
+    flags 0x{:x}",
+                        seg.cmd_size,
+                        segname,
+                        seg.vm_addr,
+                        seg.vm_size,
+                        seg.file_off,
+                        seg.file_size,
+                        seg.max_prot,
+                        seg.init_prot,
+                        seg.num_sections,
+                        seg.flags,
+                    )
+                    .unwrap();
+                }
+                LoadCommand::Dylib(_dylib) => {
+                    unreachable!();
+                }
+                LoadCommand::Uuid(uuid) => {
+                    let id = uuid::Uuid::from_bytes(uuid.uuid);
+                    let mut uuid_buf = [0u8; uuid::fmt::Hyphenated::LENGTH];
+                    let uuid_str = id.hyphenated().encode_upper(&mut uuid_buf);
+
+                    write!(
+                        &mut actual,
+                        "
+     cmd LC_UUID
+ cmdsize {}
+    uuid {uuid_str}
+",
+                        uuid.cmd_size,
+                    )
+                    .unwrap();
+                }
+                LoadCommand::DylinkerCommand(dy_cmd) => {
+                    write!(
+                        &mut actual,
+                        "
+          cmd LC_LOAD_DYLINKER
+      cmdsize {}
+         name {} (offset {})",
+                        dy_cmd.cmd_size, dy_cmd.name, dy_cmd.name_offset,
+                    )
+                    .unwrap();
+                }
+            }
+        }
+    }
+
+    similar_asserts::assert_eq!(expected, actual);
+}