On 08/08/2017 13:20, Dr. David Alan Gilbert wrote: > * Markus Armbruster (arm...@redhat.com) wrote: >> Signed-off-by: Markus Armbruster <arm...@redhat.com> >> --- >> monitor.c | 75 >> +++++++++++++++++++++++++++++++++++++++------------------------ >> 1 file changed, 47 insertions(+), 28 deletions(-) >> >> diff --git a/monitor.c b/monitor.c >> index e0f8801..8b54ba1 100644 >> --- a/monitor.c >> +++ b/monitor.c >> @@ -85,37 +85,56 @@ >> #endif >> >> /* >> - * Supported types: >> + * Command handlers (mon_cmd_t member @cmd) receive actual arguments >> + * in a QDict, which is built by the HMP core according to mon_cmd_t >> + * member @args_type. It's a list of NAME:TYPE separated by comma. >> * >> - * 'F' filename >> - * 'B' block device name >> - * 's' string (accept optional quote) >> - * 'S' it just appends the rest of the string (accept optional >> quote) >> - * 'O' option string of the form NAME=VALUE,... >> - * parsed according to QemuOptsList given by its name >> - * Example: 'device:O' uses qemu_device_opts. >> - * Restriction: only lists with empty desc are supported >> - * TODO lift the restriction >> - * 'i' 32 bit integer >> - * 'l' target long (32 or 64 bit) >> - * 'M' Non-negative target long (32 or 64 bit), in user mode the >> - * value is multiplied by 2^20 (think Mebibyte) >> - * 'o' octets (aka bytes) >> - * user mode accepts an optional E, e, P, p, T, t, G, g, M, m, >> - * K, k suffix, which multiplies the value by 2^60 for >> suffixes E >> - * and e, 2^50 for suffixes P and p, 2^40 for suffixes T and t, >> - * 2^30 for suffixes G and g, 2^20 for M and m, 2^10 for K and >> k >> - * 'T' double >> - * user mode accepts an optional ms, us, ns suffix, >> - * which divides the value by 1e3, 1e6, 1e9, respectively >> - * '/' optional gdb-like print format (like "/10x") >> + * TYPEs that put a string value with key NAME into the QDict: >> + * 's' Argument is enclosed in '"' or delimited by whitespace. In >> + * the former case, escapes \n \r \\ \' and \" are recognized. >> + * 'F' File name, like 's' except for completion. >> + * 'B' BlockBackend name, like 's' except for completion. >> + * 'S' Argument is the remainder of the line, less leading >> + * whitespace. >> + >> * >> - * '?' optional type (for all types, except '/') >> - * '.' other form of optional type (for 'i' and 'l') >> - * 'b' boolean >> - * user mode accepts "on" or "off" >> - * '-' optional parameter (eg. '-f') >> + * TYPEs that put an int64_t value with key NAME: >> + * 'l' Argument is an expression (QEMU pocket calculator). >> + * 'i' Like 'l' except value must fit into 32 bit unsigned. >> + * 'M' Like 'l' except value must not be negative and is multiplied >> + * by 2^20 (think "mebibyte"). >> * >> + * TYPEs that put an uint64_t value with key NAME: >> + * 'o' Argument is a size (think "octets"). Without suffix the >> + * value is multiplied by 2^20 (mebibytes), with suffix E or e >> + * by 2^60 (exbibytes), with P or p by 2^50 (pebibytes), with T >> + * or t by 2^40 (tebibytes), with G or g by 2^30 (gibibytes), >> + * with M or m by 2^10 (mebibytes), with K or k by 2^10 >> + * (kibibytes). > > 'o' is messy. It using qemu_strtosz_MiB which uses a 'double' intermediate > so I fear it can round. It also has a note it can't take all f's due to > an overflow from the conversion. Two things not mentioned are that > it also takes hex (as explicit 0x) and that it also does 'b' as a suffix > to multiply by 1. Those two combine in bad ways - i.e. 0x1b is 27MB, > 1b is 1 byte (same for 'e'). These are probably OK except if you were > to start replacing 'l' by 'o' because you really wanted 64bit addresses > say. > (I also wouldn't bother expanding the size names and powers). > >> + * >> + * TYPEs that put a double value with key NAME: >> + * 'T' Argument is a time in seconds. With optional ms, us, ns >> + * suffix, the value divided by 1e3, 1e6, 1e9 respectively. >> + * >> + * TYPEs that put a bool value with key NAME: >> + * 'b' Argument is either "on" (true) or "off" (false). >> + * '-' CHAR >> + * Argument is either "-CHAR" (true) or absent (false). > > I found the previous description clearer. > >> + * TYPEs that put multiple values: >> + * 'O' Option string of the form NAME=VALUE,... parsed according to >> + * the QemuOptsList given by its name. >> + * Example: 'device:O' uses qemu_device_opts. >> + * Restriction: only lists with empty desc are supported. >> + * Puts all the NAME=VALUE. >> + * '/' Gdb-like print format (like "/10x"), always optional. >> + * Puts keys "count", "format", "size", all int. >> + * >> + * Modifier character following the type string: >> + * '?' Argument is optional, nothing is put when it is absent >> + * (all types except 'O', '/', 'b'). >> + * '.' Argument is optional, must be preceded by '.' if present >> + * (only types 'i', 'l', 'M') > > That's obscure; I can only see one use of it in ioport_read and that's > extra-special!
It seems like the idea is that ioport_read 0x70.0xc is expanded to write 0xc to 0x70 read from 0x71 I can see how it can be useful for both RTC and VGA I/O ports, but on the other hand ioport_write doesn't support it and as you said it's really obscure. I guess it can be removed or changed to not use "?", though it's such a nice little nugget. :) Paolo