[ATfE] LLVM libc semihosting support for file IO - #1041
Open
voltur01 wants to merge 1 commit into
Open
Conversation
This provides the semihosting implementation for the new LLVM libc file IO embedding API as discussed in https://discourse.llvm.org/t/rfc-llvm-libc-bare-metal-file-io-support-prototype/91662 The following embedding API libc/src/__support/OSUtil/baremetal/io.h functions are implemented: - __llvm_libc_stdio_open - __llvm_libc_stdio_close - __llvm_libc_stdio_seek - __llvm_libc_stdio_set_buffer - __llvm_libc_stdio_flush - __llvm_libc_stdio_ungetc - __llvm_libc_stdio_remove - __llvm_libc_stdio_rename __llvm_libc_stdio_ungetc is not provided since the semihosting implementation is unbuffered, so the original LLVM libc single char ungetc behavior is kept. The semihosting implementation keeps a small struct as the cookie with either just the semihosting handle for standard streams or also current position to support seeking for file streams.
Contributor
Author
|
Depends on the LLVM libc embedding API: llvm/llvm-project#221211 |
vhscampos
self-requested a review
September 7, 2026 08:54
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
1 participant
Add this suggestion to a batch that can be applied as a single commit.This suggestion is invalid because no changes were made to the code.Suggestions cannot be applied while the pull request is closed.Suggestions cannot be applied while viewing a subset of changes.Only one suggestion per line can be applied in a batch.Add this suggestion to a batch that can be applied as a single commit.Applying suggestions on deleted lines is not supported.You must change the existing code in this line in order to create a valid suggestion.Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be applied on multi-line comments.Suggestions cannot be applied while the pull request is queued to merge.Suggestion cannot be applied right now. Please check back later.
This provides the semihosting implementation for the new LLVM libc file IO embedding API as discussed in https://discourse.llvm.org/t/rfc-llvm-libc-bare-metal-file-io-support-prototype/91662
The following embedding API libc/src/__support/OSUtil/baremetal/io.h functions are implemented:
__llvm_libc_stdio_ungetc is not provided since the semihosting implementation is unbuffered, so the original LLVM libc single char ungetc behavior is kept.
The semihosting implementation keeps a small struct as the cookie with either just the semihosting handle for standard streams or also current position to support seeking for file streams.