[I] `ArrowArrayStreamReader` panics on a C stream with a NULL `get_schema` or `get_next` callback [arrow-rs]

["AndreaBozzo (via GitHub)" <gi...@apache.org>]

AndreaBozzo opened a new issue, #11388:
URL: https://github.com/apache/arrow-rs/issues/11388

   ### Describe the bug
   
   `ArrowArrayStreamReader` panics when an imported C stream has a NULL `get_schema` or `get_next` callback. `try_new` returns `ArrowError::CDataInterface` for a released stream, but then calls `get_schema.unwrap()`, and `next()` calls `get_next.unwrap()` (`arrow-array/src/ffi_stream.rs:443` and `:497` on main, `:371` and `:425` in 60.0.0). A NULL `get_last_error` is already handled: the reader returns the error without a producer message.
   
   The C Stream Interface marks both callbacks *Mandatory*, so a NULL one is a producer error, and the reader should report it as one. If the reader is then re-exported with `FFI_ArrowArrayStream::new`, the panic happens inside the exported `extern "C"` `get_next` and aborts the process, which is the situation described in #8913.
   
   ### To Reproduce
   
   Against main (103ebe754), with the `ffi` feature:
   
   ```rust
   use std::ffi::c_int;
   
   use arrow::datatypes::{DataType, Field, Schema};
   use arrow::ffi::FFI_ArrowSchema;
   use arrow::ffi_stream::{ArrowArrayStreamReader, FFI_ArrowArrayStream};
   
   unsafe extern "C" fn get_schema(_: *mut FFI_ArrowArrayStream, out: *mut FFI_ArrowSchema) -> c_int {
       let schema = Schema::new(vec![Field::new("a", DataType::Int32, false)]);
       unsafe { out.write(FFI_ArrowSchema::try_from(&schema).unwrap()) };
       0
   }
   
   unsafe extern "C" fn release(stream: *mut FFI_ArrowArrayStream) {
       unsafe { (*stream).set_release(None) };
   }
   
   fn main() {
       // Stands in for a C producer that leaves get_next NULL.
       let stream = unsafe {
           FFI_ArrowArrayStream::new_unchecked(Some(get_schema), None, None, Some(release), std::ptr::null_mut())
       };
       let mut reader = ArrowArrayStreamReader::try_new(stream).unwrap();
       let _ = reader.next(); // panics: called `Option::unwrap()` on a `None` value
   }
   ```
   
   Passing `None` for `get_schema` as well makes `try_new` itself panic, at `ffi_stream.rs:443`.
   
   ### Expected behavior
   
   Both cases return `ArrowError::CDataInterface`, as `try_new` already does for a released stream, in line with #6737.
   
   ### Additional context
   
   Found while running C Stream consumers against defective producers with [arrow-abi-doctor](https://github.com/AndreaBozzo/arrow-abi-doctor). I am happy to open the PR: replace both unwraps with `CDataInterface` errors and add a test for each callback.
   


-- 
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.

To unsubscribe, e-mail: github-unsubscribe@arrow.apache.org.apache.org

For queries about this service, please contact Infrastructure at:
users@infra.apache.org

Re: [I] `ArrowArrayStreamReader` panics on a C stream with a NULL `get_schema` or `get_next` callback [arrow-rs]

["dhruv-dagar (via GitHub)" <gi...@apache.org>]

dhruv-dagar commented on issue #11388:
URL: https://github.com/apache/arrow-rs/issues/11388#issuecomment-6051856526

   .take-issue


-- 
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.

To unsubscribe, e-mail: github-unsubscribe@arrow.apache.org

For queries about this service, please contact Infrastructure at:
users@infra.apache.org

Re: [I] `ArrowArrayStreamReader` panics on a C stream with a NULL `get_schema` or `get_next` callback [arrow-rs]

["dhruv-dagar (via GitHub)" <gi...@apache.org>]

dhruv-dagar commented on issue #11388:
URL: https://github.com/apache/arrow-rs/issues/11388#issuecomment-6033455203

   /assign


-- 
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.

To unsubscribe, e-mail: github-unsubscribe@arrow.apache.org

For queries about this service, please contact Infrastructure at:
users@infra.apache.org

Re: [I] `ArrowArrayStreamReader` panics on a C stream with a NULL `get_schema` or `get_next` callback [arrow-rs]

["Jefffrey (via GitHub)" <gi...@apache.org>]

Jefffrey closed issue #11388: `ArrowArrayStreamReader` panics on a C stream with a NULL `get_schema` or `get_next` callback
URL: https://github.com/apache/arrow-rs/issues/11388


-- 
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.

To unsubscribe, e-mail: github-unsubscribe@arrow.apache.org

For queries about this service, please contact Infrastructure at:
users@infra.apache.org