By using a special type we can more naturally express flags in different programming languages. For example OCaml will prefer an optional argument containing a list of flags, defaulting to the empty list: pread [...] ?(flags = []) --- generator/generator | 66 +++++++++++++++++++++++++----------- python/t/400-pread.py | 2 +- python/t/410-pwrite.py | 2 +- python/t/460-block-status.py | 4 +-- python/t/500-aio-pread.py | 2 +- python/t/510-aio-pwrite.py | 2 +- 6 files changed, 53 insertions(+), 25 deletions(-) diff --git a/generator/generator b/generator/generator index 9f107dc..5d46938 100755 --- a/generator/generator +++ b/generator/generator @@ -820,6 +820,7 @@ and arg = | BytesPersistIn of string * string (* same as above, but buffer persists *) | BytesPersistOut of string * string | Callback of string * arg list (* callback function returning void *) +| Flags of string (* NBD_CMD_FLAG_* flags *) | Int of string (* small int *) | Int64 of string (* 64 bit signed int *) | Opaque of string (* opaque object, void* in C *) @@ -1225,7 +1226,7 @@ with the server."; "pread", { default_call with - args = [ BytesOut ("buf", "count"); UInt64 "offset"; UInt32 "flags" ]; + args = [ BytesOut ("buf", "count"); UInt64 "offset"; Flags "flags" ]; ret = RErr; shortdesc = "read from the NBD server"; longdesc = "\ @@ -1241,7 +1242,7 @@ protocol extensions)."; "pwrite", { default_call with - args = [ BytesIn ("buf", "count"); UInt64 "offset"; UInt32 "flags" ]; + args = [ BytesIn ("buf", "count"); UInt64 "offset"; Flags "flags" ]; ret = RErr; shortdesc = "write to the NBD server"; longdesc = "\ @@ -1276,7 +1277,7 @@ C<nbd_aio_disconnect>."; "flush", { default_call with - args = [ UInt32 "flags" ]; ret = RErr; + args = [ Flags "flags" ]; ret = RErr; shortdesc = "flushing pending write requests"; longdesc = "\ Issue the flush command to the NBD server. The function should @@ -1290,7 +1291,7 @@ protocol extensions)."; "trim", { default_call with - args = [ UInt64 "count"; UInt64 "offset"; UInt32 "flags" ]; + args = [ UInt64 "count"; UInt64 "offset"; Flags "flags" ]; ret = RErr; shortdesc = "send trim to the NBD server"; longdesc = "\ @@ -1309,7 +1310,7 @@ C<nbd_can_fua>)."; "cache", { default_call with - args = [ UInt64 "count"; UInt64 "offset"; UInt32 "flags" ]; + args = [ UInt64 "count"; UInt64 "offset"; Flags "flags" ]; ret = RErr; shortdesc = "send cache (prefetch) to the NBD server"; longdesc = "\ @@ -1326,7 +1327,7 @@ protocol extensions)."; "zero", { default_call with - args = [ UInt64 "count"; UInt64 "offset"; UInt32 "flags" ]; + args = [ UInt64 "count"; UInt64 "offset"; Flags "flags" ]; ret = RErr; shortdesc = "send write zeroes to the NBD server"; longdesc = "\ @@ -1353,7 +1354,7 @@ punching a hole."; UInt64 "offset"; ArrayAndLen (UInt32 "entries", "nr_entries")]); - UInt32 "flags" ]; + Flags "flags" ]; ret = RErr; shortdesc = "read the block status of the given range"; longdesc = "\ @@ -1483,7 +1484,7 @@ on the connection."; "aio_pread", { default_call with args = [ BytesPersistOut ("buf", "count"); UInt64 "offset"; - UInt32 "flags" ]; + Flags "flags" ]; ret = RInt64; shortdesc = "read from the NBD server"; longdesc = "\ @@ -1497,7 +1498,7 @@ parameters behave as documented in C<nbd_pread>."; "aio_pwrite", { default_call with - args = [ BytesPersistIn ("buf", "count"); UInt64 "offset"; UInt32 "flags" ]; + args = [ BytesPersistIn ("buf", "count"); UInt64 "offset"; Flags "flags" ]; ret = RInt64; shortdesc = "write to the NBD server"; longdesc = "\ @@ -1511,7 +1512,7 @@ parameters behave as documented in C<nbd_pwrite>."; "aio_disconnect", { default_call with - args = [ UInt32 "flags" ]; ret = RErr; + args = [ Flags "flags" ]; ret = RErr; shortdesc = "disconnect from the NBD server"; longdesc = "\ Issue the disconnect command to the NBD server. This is @@ -1526,7 +1527,7 @@ however, C<nbd_shutdown> will call this function if appropriate."; "aio_flush", { default_call with - args = [ UInt32 "flags" ]; ret = RInt64; + args = [ Flags "flags" ]; ret = RInt64; shortdesc = "send flush command to the NBD server"; longdesc = "\ Issue the flush command to the NBD server. This returns the @@ -1538,7 +1539,7 @@ in C<nbd_flush>."; "aio_trim", { default_call with - args = [ UInt64 "count"; UInt64 "offset"; UInt32 "flags" ]; + args = [ UInt64 "count"; UInt64 "offset"; Flags "flags" ]; ret = RInt64; shortdesc = "send trim to the NBD server"; longdesc = "\ @@ -1551,7 +1552,7 @@ in C<nbd_trim>."; "aio_cache", { default_call with - args = [ UInt64 "count"; UInt64 "offset"; UInt32 "flags" ]; + args = [ UInt64 "count"; UInt64 "offset"; Flags "flags" ]; ret = RInt64; shortdesc = "send cache (prefetch) to the NBD server"; longdesc = "\ @@ -1564,7 +1565,7 @@ in C<nbd_cache>."; "aio_zero", { default_call with - args = [ UInt64 "count"; UInt64 "offset"; UInt32 "flags" ]; + args = [ UInt64 "count"; UInt64 "offset"; Flags "flags" ]; ret = RInt64; shortdesc = "send write zeroes to the NBD server"; longdesc = "\ @@ -1583,7 +1584,7 @@ in C<nbd_zero>."; UInt64 "offset"; ArrayAndLen (UInt32 "entries", "nr_entries")]); - UInt32 "flags" ]; + Flags "flags" ]; ret = RInt64; shortdesc = "send block status to the NBD server"; longdesc = "\ @@ -2494,6 +2495,21 @@ let generate_lib_states_c () = (* Generate C API. *) +(* Check the API definition. *) +let () = + (* Flags must only appear once in the final argument position. *) + List.iter ( + fun (name, { args }) -> + let args = List.rev args in + match args with + | [] -> () + | Flags _ :: xs + | xs -> + if List.exists (function Flags _ -> true | _ -> false) xs then + failwithf "%s: Flags must appear in final argument position only" + name + ) handle_calls + let generate_lib_libnbd_syms () = generate_header HashStyle; @@ -2517,6 +2533,7 @@ let rec name_of_arg = function | BytesPersistIn (n, len) -> [n; len] | BytesPersistOut (n, len) -> [n; len] | Callback (n, _) -> [n] +| Flags n -> [n] | Int n -> [n] | Int64 n -> [n] | Opaque n -> [n] @@ -2548,6 +2565,7 @@ let rec print_c_arg_list ?(handle = false) args = | BytesOut (n, len) | BytesPersistOut (n, len) -> pr "void *%s, size_t %s" n len | Callback (n, args) -> pr "void (*%s) " n; print_c_arg_list args + | Flags n -> pr "uint32_t %s" n | Int n -> pr "int %s" n | Int64 n -> pr "int64_t %s" n | Opaque n -> pr "void *%s" n @@ -2950,7 +2968,7 @@ let print_python_binding name { args; ret } = | UInt64 n -> () (* The following not yet implemented for callbacks XXX *) | ArrayAndLen _ | Bool _ | BytesIn _ | BytesOut _ - | BytesPersistIn _ | BytesPersistOut _ | Callback _ + | BytesPersistIn _ | BytesPersistOut _ | Callback _ | Flags _ | Int _ | Int64 _ | Path _ | SockAddrAndLen _ | StringList _ | UInt _ | UInt32 _ -> pr " abort ();\n" ) args; @@ -2965,7 +2983,7 @@ let print_python_binding name { args; ret } = | UInt64 n -> pr " \"K\"" (* The following not yet implemented for callbacks XXX *) | ArrayAndLen _ | Bool _ | BytesIn _ | BytesOut _ - | BytesPersistIn _ | BytesPersistOut _ | Callback _ + | BytesPersistIn _ | BytesPersistOut _ | Callback _ | Flags _ | Int _ | Int64 _ | Path _ | SockAddrAndLen _ | StringList _ | UInt _ | UInt32 _ -> pr " abort ();\n" ) args; @@ -2978,7 +2996,7 @@ let print_python_binding name { args; ret } = | UInt64 n -> pr ", %s" n (* The following not yet implemented for callbacks XXX *) | ArrayAndLen _ | Bool _ | BytesIn _ | BytesOut _ - | BytesPersistIn _ | BytesPersistOut _ | Callback _ + | BytesPersistIn _ | BytesPersistOut _ | Callback _ | Flags _ | Int _ | Int64 _ | Path _ | SockAddrAndLen _ | StringList _ | UInt _ | UInt32 _ -> pr " abort ();\n" ) args; @@ -3009,7 +3027,7 @@ let print_python_binding name { args; ret } = | Opaque _ -> () (* The following not yet implemented for callbacks XXX *) | ArrayAndLen _ | Bool _ | BytesIn _ | BytesOut _ - | BytesPersistIn _ | BytesPersistOut _ | Callback _ + | BytesPersistIn _ | BytesPersistOut _ | Callback _ | Flags _ | Int _ | Int64 _ | Path _ | SockAddrAndLen _ | StringList _ | UInt _ | UInt32 _ -> () ) args; @@ -3054,6 +3072,9 @@ let print_python_binding name { args; ret } = pr " struct py_aio_buffer *%s_buf;\n" n | Callback (n, _) -> pr " struct %s_%s_data callback_data;\n" name n + | Flags n -> + pr " uint32_t %s_u32;\n" n; + pr " unsigned int %s = 0; /* really uint32_t */\n" n | Int n -> pr " int %s;\n" n | Int64 n -> pr " int64_t %s_i64;\n" n; @@ -3091,6 +3112,7 @@ let print_python_binding name { args; ret } = | BytesOut (_, count) -> pr " \"n\"" | BytesPersistOut (_, count) -> pr " \"O\"" | Callback (n, _) -> pr " \"O\"" + | Flags n -> pr " \"|I\"" | Int n -> pr " \"i\"" | Int64 n -> pr " \"L\"" | Opaque _ -> pr " \"O\"" @@ -3114,6 +3136,7 @@ let print_python_binding name { args; ret } = | BytesPersistOut (n, _) -> pr ", &%s" n | BytesOut (_, count) -> pr ", &%s" count | Callback _ -> pr ", &callback_data.fn" + | Flags n -> pr ", &%s" n | Int n -> pr ", &%s" n | Int64 n -> pr ", &%s" n | Opaque n -> pr ", &%s" n @@ -3162,6 +3185,7 @@ let print_python_binding name { args; ret } = n; pr " return NULL;\n"; pr " }\n" + | Flags n -> pr " %s_u32 = %s;\n" n n | Int _ -> () | Int64 n -> pr " %s_i64 = %s;\n" n n | Opaque n -> @@ -3190,6 +3214,7 @@ let print_python_binding name { args; ret } = | BytesPersistIn (n, _) | BytesPersistOut (n, _) -> pr ", %s_buf->data, %s_buf->len" n n | Callback (n, _) -> pr ", %s_%s_wrapper" name n + | Flags n -> pr ", %s_u32" n | Int n -> pr ", %s" n | Int64 n -> pr ", %s_i64" n | Opaque _ -> pr ", &callback_data" @@ -3223,6 +3248,7 @@ let print_python_binding name { args; ret } = | BytesIn _ | BytesPersistIn _ | BytesPersistOut _ | Callback _ + | Flags _ | Int _ | Int64 _ | Opaque _ @@ -3264,6 +3290,7 @@ let print_python_binding name { args; ret } = | BytesIn (n, _) -> pr " PyBuffer_Release (&%s);\n" n | BytesPersistIn _ | BytesOut _ | BytesPersistOut _ -> () | Callback _ -> () + | Flags _ -> () | Int _ -> () | Int64 _ -> () | Opaque _ -> () @@ -3359,6 +3386,7 @@ class NBD (object): | BytesPersistOut (n, _) -> n | BytesOut (_, count) -> count | Callback (n, _) -> n + | Flags n -> n ^ "=0" | Int n -> n | Int64 n -> n | Opaque n -> n diff --git a/python/t/400-pread.py b/python/t/400-pread.py index da4799b..4d64166 100644 --- a/python/t/400-pread.py +++ b/python/t/400-pread.py @@ -20,7 +20,7 @@ import nbd h = nbd.NBD () h.connect_command (["nbdkit", "-s", "--exit-with-parent", "-v", "pattern", "size=512"]) -buf = h.pread (512, 0, 0) +buf = h.pread (512, 0) print ("%r" % buf) diff --git a/python/t/410-pwrite.py b/python/t/410-pwrite.py index 9152ba2..811f233 100644 --- a/python/t/410-pwrite.py +++ b/python/t/410-pwrite.py @@ -33,7 +33,7 @@ h = nbd.NBD () h.connect_command (["nbdkit", "-s", "--exit-with-parent", "-v", "file", datafile]) h.pwrite (buf1, 0, nbd.CMD_FLAG_FUA) -buf2 = h.pread (512, 0, 0) +buf2 = h.pread (512, 0) assert buf1 == buf2 diff --git a/python/t/460-block-status.py b/python/t/460-block-status.py index f511091..eeaa7b2 100644 --- a/python/t/460-block-status.py +++ b/python/t/460-block-status.py @@ -34,14 +34,14 @@ def f (data, metacontext, offset, e): return entries = e -h.block_status (65536, 0, 42, f, 0) +h.block_status (65536, 0, 42, f) assert entries == [ 8192, 0, 8192, 1, 16384, 3, 16384, 2, 16384, 0] -h.block_status (1024, 32256, 42, f, 0) +h.block_status (1024, 32256, 42, f) print ("entries = %r" % entries) assert entries == [ 512, 3, 16384, 2] diff --git a/python/t/500-aio-pread.py b/python/t/500-aio-pread.py index 82199ef..85342f5 100644 --- a/python/t/500-aio-pread.py +++ b/python/t/500-aio-pread.py @@ -21,7 +21,7 @@ h = nbd.NBD () h.connect_command (["nbdkit", "-s", "--exit-with-parent", "-v", "pattern", "size=512"]) buf = nbd.aio_buffer (512) -id = h.aio_pread (buf, 0, 0) +id = h.aio_pread (buf, 0) while not (h.aio_command_completed (id)): h.poll (-1) diff --git a/python/t/510-aio-pwrite.py b/python/t/510-aio-pwrite.py index b73464b..4770b83 100644 --- a/python/t/510-aio-pwrite.py +++ b/python/t/510-aio-pwrite.py @@ -39,7 +39,7 @@ while not (h.aio_command_completed (id)): h.poll (-1) buf2 = nbd.aio_buffer (512) -id = h.aio_pread (buf2, 0, 0) +id = h.aio_pread (buf2, 0) while not (h.aio_command_completed (id)): h.poll (-1) -- 2.21.0