Re: [PATCH 01/18] qapi: Smarter camel_to_upper() to reduce need for 'prefix'

[Daniel P . Berrangé]

On Tue, Jul 30, 2024 at 10:10:15AM +0200, Markus Armbruster wrote:
> camel_to_upper() converts its argument from camel case to upper case
> with '_' between words.  Used for generated enumeration constant
> prefixes.
> 
> When some of the words are spelled all caps, where exactly to insert
> '_' is guesswork.  camel_to_upper()'s guesses are bad enough in places
> to make people override them with a 'prefix' in the schema.
> 
> Rewrite it to guess better:
> 
> 1. Insert '_' after a non-upper case character followed by an upper
>    case character:
> 
>        OneTwo -> ONE_TWO
>        One2Three -> ONE2_THREE
> 
> 2. Insert '_' before the last upper case character followed by a
>    non-upper case character:
> 
>        ACRONYMWord -> ACRONYM_Word
> 
>    Except at the beginning (as in OneTwo above), or when there is
>    already one:
> 
>        AbCd -> AB_CD
> 
> This changes the default enumeration constant prefix for a number of
> enums.  Generated enumeration constants change only where the default
> is not overridden with 'prefix'.
> 
> The following enumerations without a 'prefix' change:
> 
>     enum                                  old camel_to_upper()
>                                   new camel_to_upper()
>     ------------------------------------------------------------------
>     DisplayGLMode                   DISPLAYGL_MODE
>                                   DISPLAY_GL_MODE
>     EbpfProgramID                   EBPF_PROGRAMID
>                                   EBPF_PROGRAM_ID
>     HmatLBDataType                  HMATLB_DATA_TYPE
>                                   HMAT_LB_DATA_TYPE
>     HmatLBMemoryHierarchy           HMATLB_MEMORY_HIERARCHY
>                                   HMAT_LB_MEMORY_HIERARCHY
>     MultiFDCompression              MULTIFD_COMPRESSION
>                                   MULTI_FD_COMPRESSION
>     OffAutoPCIBAR                   OFF_AUTOPCIBAR
>                                   OFF_AUTO_PCIBAR
>     QCryptoBlockFormat              Q_CRYPTO_BLOCK_FORMAT
>                                   QCRYPTO_BLOCK_FORMAT
>     QCryptoBlockLUKSKeyslotState    Q_CRYPTO_BLOCKLUKS_KEYSLOT_STATE
>                                   QCRYPTO_BLOCK_LUKS_KEYSLOT_STATE
>     QKeyCode                        Q_KEY_CODE
>                                   QKEY_CODE
>     XDbgBlockGraphNodeType          X_DBG_BLOCK_GRAPH_NODE_TYPE
>                                   XDBG_BLOCK_GRAPH_NODE_TYPE
>     TestUnionEnumA                TEST_UNION_ENUMA
>                                   TEST_UNION_ENUM_A
> 
> Add a 'prefix' so generated code doesn't change now.  Subsequent
> commits will remove most of them again.  Two will remain:
> MULTIFD_COMPRESSION, because migration code generally spells "multifd"
> that way, and Q_KEY_CODE, because that one is baked into
> subprojects/keycodemapdb/tools/keymap-gen.
> 
> The following enumerations with a 'prefix' change so that the prefix
> is now superfluous:
> 
>     enum                                  old camel_to_upper()
>                                   new camel_to_upper() [equal to prefix]
>     ------------------------------------------------------------------
>     BlkdebugIOType                  BLKDEBUGIO_TYPE
>                                   BLKDEBUG_IO_TYPE
>     QCryptoTLSCredsEndpoint         Q_CRYPTOTLS_CREDS_ENDPOINT
>                                   QCRYPTO_TLS_CREDS_ENDPOINT
>     QCryptoSecretFormat             Q_CRYPTO_SECRET_FORMAT
>                                   QCRYPTO_SECRET_FORMAT
>     QCryptoCipherMode               Q_CRYPTO_CIPHER_MODE
>                                   QCRYPTO_CIPHER_MODE
>     QCryptodevBackendType           Q_CRYPTODEV_BACKEND_TYPE
>                                   QCRYPTODEV_BACKEND_TYPE
>     QType [builtin]                 Q_TYPE
>                                   QTYPE
> 
> Drop these prefixes.
> 
> The following enumerations with a 'prefix' change without making the
> 'prefix' superfluous:
> 
>     enum                                  old camel_to_upper()
>                                   new camel_to_upper() [equal to prefix]
>                                   prefix
>     ------------------------------------------------------------------
>     CpuS390Entitlement              CPUS390_ENTITLEMENT
>                                   CPU_S390_ENTITLEMENT
>                                   S390_CPU_ENTITLEMENT
>     CpuS390Polarization             CPUS390_POLARIZATION
>                                   CPU_S390_POLARIZATION
>                                   S390_CPU_POLARIZATION
>     CpuS390State                    CPUS390_STATE
>                                   CPU_S390_STATE
>                                   S390_CPU_STATE
>     QAuthZListFormat                Q_AUTHZ_LIST_FORMAT
>                                   QAUTH_Z_LIST_FORMAT
>                                   QAUTHZ_LIST_FORMAT
>     QAuthZListPolicy                Q_AUTHZ_LIST_POLICY
>                                   QAUTH_Z_LIST_POLICY
>                                   QAUTHZ_LIST_POLICY
>     QCryptoAkCipherAlgorithm        Q_CRYPTO_AK_CIPHER_ALGORITHM
>                                   QCRYPTO_AK_CIPHER_ALGORITHM
>                                   QCRYPTO_AKCIPHER_ALG
>     QCryptoAkCipherKeyType          Q_CRYPTO_AK_CIPHER_KEY_TYPE
>                                   QCRYPTO_AK_CIPHER_KEY_TYPE
>                                   QCRYPTO_AKCIPHER_KEY_TYPE
>     QCryptoCipherAlgorithm          Q_CRYPTO_CIPHER_ALGORITHM
>                                   QCRYPTO_CIPHER_ALGORITHM
>                                   QCRYPTO_CIPHER_ALG
>     QCryptoHashAlgorithm            Q_CRYPTO_HASH_ALGORITHM
>                                   QCRYPTO_HASH_ALGORITHM
>                                   QCRYPTO_HASH_ALG
>     QCryptoIVGenAlgorithm           Q_CRYPTOIV_GEN_ALGORITHM
>                                   QCRYPTO_IV_GEN_ALGORITHM
>                                   QCRYPTO_IVGEN_ALG
>     QCryptoRSAPaddingAlgorithm      Q_CRYPTORSA_PADDING_ALGORITHM
>                                   QCRYPTO_RSA_PADDING_ALGORITHM
>                                   QCRYPTO_RSA_PADDING_ALG
>     QCryptodevBackendAlgType        Q_CRYPTODEV_BACKEND_ALG_TYPE
>                                   QCRYPTODEV_BACKEND_ALG_TYPE
>                                   QCRYPTODEV_BACKEND_ALG
>     QCryptodevBackendServiceType    Q_CRYPTODEV_BACKEND_SERVICE_TYPE
>                                   QCRYPTODEV_BACKEND_SERVICE_TYPE
>                                   QCRYPTODEV_BACKEND_SERVICE
> 
> Subsequent commits will tweak things to remove most of these prefixes.
> Only QAUTHZ_LIST_FORMAT and QAUTHZ_LIST_POLICY will remain.

IIUC from above those two result in 

                            QAUTH_Z_LIST_FORMAT
                            QAUTH_Z_LIST_POLICY

Is it possible to add a 3rd rule

 *  Single uppercase letter folds into the previous word

or are there valid cases where we have a single uppercase
that we want to preserve ?

It sure would be nice to eliminate the 'prefix' concept,
that we've clearly over-used, if we can kill the only 2
remaining examples.

> 
> Signed-off-by: Markus Armbruster <armbru@redhat.com>
> ---
>  qapi/block-core.json                     |  3 +-
>  qapi/common.json                         |  1 +
>  qapi/crypto.json                         |  6 ++--
>  qapi/cryptodev.json                      |  1 -
>  qapi/ebpf.json                           |  1 +
>  qapi/machine.json                        |  1 +
>  qapi/migration.json                      |  1 +
>  qapi/ui.json                             |  2 ++
>  scripts/qapi/common.py                   | 42 ++++++++++++++----------
>  scripts/qapi/schema.py                   |  2 +-
>  tests/qapi-schema/alternate-array.out    |  1 -
>  tests/qapi-schema/comments.out           |  1 -
>  tests/qapi-schema/doc-good.out           |  1 -
>  tests/qapi-schema/empty.out              |  1 -
>  tests/qapi-schema/include-repetition.out |  1 -
>  tests/qapi-schema/include-simple.out     |  1 -
>  tests/qapi-schema/indented-expr.out      |  1 -
>  tests/qapi-schema/qapi-schema-test.json  |  1 +
>  tests/qapi-schema/qapi-schema-test.out   |  2 +-
>  19 files changed, 37 insertions(+), 33 deletions(-)

Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>


With regards,
Daniel
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