From 3949e59414fccefadc50ae65650d676cc734048c Mon Sep 17 00:00:00 2001 From: Markus Armbruster Date: Wed, 6 Feb 2013 21:27:24 +0100 Subject: qemu-char: Saner naming of memchar stuff & doc fixes New device, has never been released, so we can still improve things without worrying about compatibility. Naming is a mess. The code calls the device driver CirMemCharDriver, the public API calls it "memory", "memchardev", or "memchar", and the special commands are named like "memchar-FOO". "memory" is a particularly unfortunate choice, because there's another character device driver called MemoryDriver. Moreover, the device's distinctive property is that it's a ring buffer, not that's in memory. Therefore: * Rename CirMemCharDriver to RingBufCharDriver, and call the thing a "ringbuf" in the API. * Rename QMP and HMP commands from memchar-FOO to ringbuf-FOO. * Rename device parameter from maxcapacity to size (simple words are good for you). * Clearly mark the parameter as optional in documentation. * Fix error reporting so that chardev-add reports to current monitor, not stderr. * Replace cirmem in C identifiers by ringbuf. * Rework documentation. Document the impact of our crappy UTF-8 handling on reading. * QMP examples that even work. I could split this up into multiple commits, but they'd change the same documentation lines multiple times. Not worth it. Signed-off-by: Markus Armbruster Reviewed-by: Eric Blake Signed-off-by: Anthony Liguori --- qmp-commands.hx | 55 +++++++++++++++++++++++++++++-------------------------- 1 file changed, 29 insertions(+), 26 deletions(-) (limited to 'qmp-commands.hx') diff --git a/qmp-commands.hx b/qmp-commands.hx index 51ce2e6b41..799adea1b7 100644 --- a/qmp-commands.hx +++ b/qmp-commands.hx @@ -466,30 +466,30 @@ Note: inject-nmi fails when the guest doesn't support injecting. EQMP { - .name = "memchar-write", + .name = "ringbuf-write", .args_type = "device:s,data:s,format:s?", - .mhandler.cmd_new = qmp_marshal_input_memchar_write, + .mhandler.cmd_new = qmp_marshal_input_ringbuf_write, }, SQMP -memchar-write +ringbuf-write ------------- -Provide writing interface for CirMemCharDriver. Write data to memory -char device. +Write to a ring buffer character device. Arguments: -- "device": the name of the char device, must be unique (json-string) -- "data": the source data write to memory (json-string) -- "format": the data format write to memory, default is - utf8. (json-string, optional) - - Possible values: "utf8", "base64" +- "device": ring buffer character device name (json-string) +- "data": data to write (json-string) +- "format": data format (json-string, optional) + - Possible values: "utf8" (default), "base64" + Bug: invalid base64 is currently not rejected. + Whitespace *is* invalid. Example: --> { "execute": "memchar-write", - "arguments": { "device": foo, +-> { "execute": "ringbuf-write", + "arguments": { "device": "foo", "data": "abcdefgh", "format": "utf8" } } <- { "return": {} } @@ -497,32 +497,35 @@ Example: EQMP { - .name = "memchar-read", + .name = "ringbuf-read", .args_type = "device:s,size:i,format:s?", - .mhandler.cmd_new = qmp_marshal_input_memchar_read, + .mhandler.cmd_new = qmp_marshal_input_ringbuf_read, }, SQMP -memchar-read +ringbuf-read ------------- -Provide read interface for CirMemCharDriver. Read from the char -device memory and return the data with size. +Read from a ring buffer character device. Arguments: -- "device": the name of the char device, must be unique (json-string) -- "size": the memory size wanted to read in bytes (refer to unencoded - size of the raw data), would adjust to the init size of the - memchar if the requested size is larger than it. (json-int) -- "format": the data format write to memchardev, default is - utf8. (json-string, optional) - - Possible values: "utf8", "base64" +- "device": ring buffer character device name (json-string) +- "size": how many bytes to read at most (json-int) + - Number of data bytes, not number of characters in encoded data +- "format": data format (json-string, optional) + - Possible values: "utf8" (default), "base64" + - Naturally, format "utf8" works only when the ring buffer + contains valid UTF-8 text. Invalid UTF-8 sequences get + replaced. Bug: replacement doesn't work. Bug: can screw + up on encountering NUL characters, after the ring buffer + lost data, and when reading stops because the size limit + is reached. Example: --> { "execute": "memchar-read", - "arguments": { "device": foo, +-> { "execute": "ringbuf-read", + "arguments": { "device": "foo", "size": 1000, "format": "utf8" } } <- {"return": "abcdefgh"} -- cgit v1.2.1