Skip to main content Crate c2pa_c Copy item path Source cimpl_error macros FFI Helper Macros utils FFI Utilities arc_tracked Create an Arc-wrapped pointer and track it
Returns the raw pointer box_tracked Create a Box-wrapped pointer and track it
Returns the raw pointer bytes_or_return Validate and convert raw C byte array to safe slice, returning early on error. bytes_or_return_int Validate and convert raw C byte array to safe slice, return -1 on error. bytes_or_return_null Validate and convert raw C byte array to safe slice, return NULL on error. cimpl_free Free a pointer that was allocated by cimpl. cstr_option Convert a *const c_char to Option<String>.
Returns None if the pointer is null.
Returns Some(String) if the pointer is not null.
Returns None if the string is too long. cstr_or_return Convert C string with bounded length check or early-return with error value.
Errors if the string exceeds MAX_CSTRING_LEN bytes. cstr_or_return_int cstr_or_return_null If the expression is null, set the last error and return std::ptr::null_mut(). cstr_or_return_with_limit Convert C string with custom length limit or early-return with error value.
Errors if the string exceeds max_len bytes. deref_mut_or_return Validate pointer and dereference mutably, returning reference
Returns early with custom value on error deref_mut_or_return_int Validate pointer and dereference mutably, returning reference
Returns -1 on error deref_mut_or_return_null Validate pointer and dereference mutably, returning reference
Returns NULL on error deref_or_return_false Validate pointer and dereference immutably, returning reference
Returns false on error deref_or_return_int Validate pointer and dereference immutably, returning reference
Returns -1 on error deref_or_return_null Validate pointer and dereference immutably, returning reference
Returns NULL on error deref_or_return_zero Validate pointer and dereference immutably, returning reference
Returns 0 on error ok_or_return Handle Result or early-return with error value ok_or_return_false Handle Result, early-return with false on error ok_or_return_int Handle Result, early-return with -1 (negative) on error ok_or_return_null Handle Result, early-return with null on error ok_or_return_zero Handle Result, early-return with 0 on error option_to_c_string Converts an Option<String> to a C string pointer.
Returns null_mut() if the Option is None. ptr_or_return Check pointer not null or early-return with error value ptr_or_return_int If the expression is null, set the last error and return -1. ptr_or_return_null If the expression is null, set the last error and return null. some_or_return Handle Option, early-return with custom value if None some_or_return_false Handle Option, early-return with false if None some_or_return_int Handle Option, early-return with -1 if None some_or_return_null Handle Option, early-return with NULL if None some_or_return_zero Handle Option, early-return with 0 if None untrack_or_return Untrack a pointer from the registry (ownership transfer from C to Rust). untrack_or_return_int Untrack a pointer from the registry, returning -1 on error. untrack_or_return_null Untrack a pointer from the registry, returning NULL on error. Builder Use a Builder to add a signed manifest to an asset. C2paHttpRequest HTTP request passed to the resolver callback. C2paHttpResolver Opaque handle for a C-callback-based HTTP resolver.
Created by c2pa_http_resolver_create(). Either consumed by
c2pa_context_builder_set_http_resolver() or freed via c2pa_free(). C2paHttpResponse HTTP response filled in by the resolver callback. C2paSigner C2paSignerInfo Defines the configuration for a Signer. C2paStream A C2paStream is a Rust Read/Write/Seek stream that can be created and used in C. Reader Use a Reader to read and validate a manifest store. SignerInfo SignerInfo provides the information needed to create a signer
and sign a manifest. StreamContext An opaque struct to hold a context value for the stream callbacks. TestC2paStream This struct is used to test the C2paStream implementation. C2paBuilderIntent Builder intent enumeration.
This specifies what kind of manifest to create. C2paDigitalSourceType List of possible digital source types. C2paError Error enumerates errors returned by most C2PA toolkit operations.C2paHashType Hash binding type for embeddable signing workflows. C2paProgressPhase Progress phase constants passed to C progress callbacks.
These mirror c2pa::ProgressPhase C2paSeekMode Defines the seek mode for the seek callback. C2paSigningAlg List of supported signing algorithms. SigningAlg Describes the digital signature algorithms allowed by the C2PA spec. AsyncSigner The AsyncSigner trait generates a cryptographic signature over a byte array. Signer The Signer trait generates a cryptographic signature over a byte array. c2pa_builder_add_action ⚠ Adds an action to the manifest the Builder is constructing. c2pa_builder_add_ingredient_from_archive ⚠ Adds an ingredient to the C2paBuilder from a C2PA ingredient archive stream. c2pa_builder_add_ingredient_from_stream ⚠ Adds an ingredient to the C2paBuilder. c2pa_builder_add_resource ⚠ Adds a resource to the C2paBuilder. c2pa_builder_data_hashed_placeholder ⚠ Creates a hashed placeholder from a Builder.
The placeholder is used to reserve size in an asset for later signing. c2pa_builder_free ⚠ Deprecated Frees a C2paBuilder allocated by Rust. c2pa_builder_from_archive ⚠ Deprecated Create a C2paBuilder from an archive stream. c2pa_builder_from_context ⚠ Creates a C2paBuilder from a shared Context. c2pa_builder_from_json ⚠ Deprecated Creates a C2paBuilder from a JSON manifest definition string. c2pa_builder_hash_mdat_bytes ⚠ Generate the mdat leaf hashes for the asset, the C2paHasher will accumulate the hash values for
each mdat_id. The data_ptr should be supplied in the order the chunks are written to the mdat.
The mdat_id should be begin with 0 and increment for each mdat in the asset. For assets with a s
ingle mdat, the mdat_id should be 0. If fixed size Merkle is enabled, the data will be accumulated
and hashed in fixed size chunks and the final chunk will be padded. Otherwise the data will be hashed
as a single leaf for each mdat chunk supplied to this call. c2pa_builder_hash_type ⚠ Returns the hash binding type that the builder will use for the given format. c2pa_builder_needs_placeholder ⚠ Returns whether a placeholder manifest is required for the given format. c2pa_builder_placeholder ⚠ Creates a composed placeholder manifest from a Builder. c2pa_builder_set_base_path ⚠ ⚠️ Deprecated Soon
This method is planned to be deprecated in a future release.
Usage should be limited and temporary. c2pa_builder_set_data_hash_exclusions ⚠ Sets the byte exclusion ranges on the DataHash assertion in a Builder. c2pa_builder_set_fixed_size_merkle ⚠ If set the hasher will hash fixed size chunks of data, padding the final block as needed.
This will produce a Merkle tree for each mdat with fixed size leaves, which can be used
for efficient hashing of large assets. c2pa_builder_set_intent ⚠ Sets the builder intent on the Builder. c2pa_builder_set_no_embed ⚠ Sets the no-embed flag on the Builder.
When set, the builder will not embed a C2PA manifest store into the asset when signing.
This is useful when creating cloud or sidecar manifests. c2pa_builder_set_remote_url ⚠ Sets the remote URL on the Builder.
When set, the builder will embed a remote URL into the asset when signing.
This is useful when creating cloud based Manifests. c2pa_builder_sign ⚠ Creates and writes signed manifest from the C2paBuilder to the destination stream. c2pa_builder_sign_context ⚠ Sign using the Signer from the Context. c2pa_builder_sign_data_hashed_embeddable ⚠ Sign a Builder using the specified signer and data hash.
The data hash is a JSON string containing DataHash information for the asset.
This is a low-level method for advanced use cases where the caller handles embedding the manifest. c2pa_builder_sign_embeddable ⚠ Signs the manifest and returns composed bytes ready for embedding. c2pa_builder_supported_mime_types ⚠ Returns an array of char* pointers to the supported mime types.
The caller is responsible for freeing the array. c2pa_builder_to_archive ⚠ Writes an Archive of the Builder to the destination stream. c2pa_builder_update_hash_from_stream ⚠ Updates the hard binding assertion in a Builder by hashing an asset stream. c2pa_builder_with_archive ⚠ Configures an existing builder with an archive stream. c2pa_builder_with_definition ⚠ Updates the builder with a new manifest definition. c2pa_builder_write_ingredient_archive ⚠ Writes a single-ingredient C2PA archive to the destination stream. c2pa_context_builder_build ⚠ Builds an immutable, shareable context from the builder. c2pa_context_builder_new ⚠ Creates a new context builder with default settings. c2pa_context_builder_set_http_resolver ⚠ Sets a custom HTTP resolver on the context builder. c2pa_context_builder_set_progress_callback ⚠ Attaches a C progress callback to a context builder. c2pa_context_builder_set_settings ⚠ Updates the builder with settings. c2pa_context_builder_set_signer ⚠ Set a Signer into the Builder’s context.
(The context will own the Signer from that point on).
The signer will be available via context.signer() after
building the context. If a signer is also configured in settings,
the programmatic signer takes priority regardless of call order. c2pa_context_cancel ⚠ Requests cancellation of any in-progress operation on this context. c2pa_context_new ⚠ Creates a new immutable context with default settings. c2pa_create_stream ⚠ Creates a new C2paStream from context with callbacks. c2pa_ed25519_sign ⚠ Signs a byte array using the Ed25519 algorithm. c2pa_error ⚠ Returns the last error message. c2pa_error_set_last ⚠ Sets the last error message.
This is used by callbacks so they can set a return error message.
THe error should be in the form of “ErrorType: ErrorMessage”.
If ErrorType is missing or invalid, it will be set to “Other”.
and the message will include the original error string.
Can return -1 if the error string is NULL. c2pa_format_embeddable ⚠ Convert a binary c2pa manifest into an embeddable version for the given format.
A raw manifest (in application/c2pa format) can be uploaded to the cloud but
it cannot be embedded directly into an asset without extra processing.
This method converts the raw manifest into an embeddable version that can be
embedded into an asset. c2pa_free ⚠ Frees any pointer allocated by this library. c2pa_free_string_array ⚠ Frees an array of char* pointers created by Rust. c2pa_http_resolver_create ⚠ Creates a new HTTP resolver backed by a C callback. c2pa_load_settings ⚠ Deprecated Load Settings from a string.
Sets thread-local settings. c2pa_manifest_bytes_free ⚠ Deprecated Frees a C2PA manifest returned by c2pa_builder_sign. c2pa_reader_detailed_json ⚠ Returns a detailed JSON string generated from a C2paReader. c2pa_reader_free ⚠ Deprecated Frees a C2paReader allocated by Rust. c2pa_reader_from_context ⚠ Creates a new C2paReader from a shared context. c2pa_reader_from_manifest_data_and_stream ⚠ Deprecated Creates and verifies a C2paReader from an asset stream with the given format and manifest data. c2pa_reader_from_stream ⚠ Deprecated Example c2pa_reader_is_embedded ⚠ Returns if the reader was created from an embedded manifest. c2pa_reader_json ⚠ Returns a JSON string generated from a C2paReader. c2pa_reader_new ⚠ Creates a new C2paReader from a default context. c2pa_reader_remote_url ⚠ Returns the remote url of the manifest if it was obtained remotely. c2pa_reader_resource_to_stream ⚠ Writes a C2paReader resource to a stream given a URI. c2pa_reader_supported_mime_types ⚠ Returns an array of char* pointers to c2pa::Reader’s supported mime types.
The caller is responsible for freeing the array. c2pa_reader_with_fragment ⚠ Configures an existing reader with a fragment stream. c2pa_reader_with_manifest_data_and_stream ⚠ Configures an existing passed in Reader with manifest data and a stream.
This covers the case when a Reader needs to be able to re-read signed
manifest bytes. This method consumes the original Reader and returns a
new configured Reader. The original Reader pointer becomes invalid after
this call and should not be reused. c2pa_reader_with_stream ⚠ Configures an existing reader with a stream. c2pa_release_stream ⚠ Releases a C2paStream allocated by Rust. c2pa_release_string ⚠ Deprecated Frees a string allocated by Rust. c2pa_settings_new ⚠ Creates a new C2PA settings object with default values. c2pa_settings_set_value ⚠ Sets a specific configuration value in the settings using dot notation. c2pa_settings_update_from_string ⚠ Updates settings from a JSON or TOML string. c2pa_signature_free ⚠ Deprecated Frees a signature allocated by Rust. c2pa_signer_create ⚠ Creates a C2paSigner from a callback and configuration. c2pa_signer_free ⚠ Deprecated Frees a C2paSigner allocated by Rust. c2pa_signer_from_info ⚠ Creates a C2paSigner from a SignerInfo.
The signer is created from the sign_cert and private_key fields.
an optional url to an RFC 3161 compliant time server will ensure the signature is timestamped. c2pa_signer_from_settings ⚠ Deprecated Creates a C2paSigner from the settings.
The signer is created from the settings defined in the c2pa_settings.json file. c2pa_signer_reserve_size ⚠ Returns the size to reserve for the signature for this signer. c2pa_string_free ⚠ Deprecated Frees a string allocated by Rust. c2pa_version ⚠ Returns a version string for logging. cimpl_free Universal free function for any tracked pointer safe_slice_from_raw_parts ⚠ Creates a safe slice from raw parts with bounds validation to_c_bytes Converts a Vec <u8> to a tracked C byte array pointer to_c_string Converts a Rust String to a C string (*mut c_char) track_arc Track an Arc-wrapped pointer track_arc_mutex Track an Arc<Mutex<T>>-wrapped pointer track_box Track a Box-wrapped pointer untrack_pointer Remove a pointer from tracking without running its cleanup function. validate_pointer Validate that a pointer is tracked and has the expected type C2paHttpResolverCallback Callback type for custom HTTP request resolution. C2paResult A specialized Result type for C2PA toolkit operations. Error ProgressCCallback C-callable progress callback function type. Result SignerCallback Defines a callback to read from a stream.