"Dr. David Alan Gilbert" <dgilb...@redhat.com> writes: > * Markus Armbruster (arm...@redhat.com) wrote: >> "Dr. David Alan Gilbert" <dgilb...@redhat.com> writes: >> >> > * 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 does, but only when you have more than 53 significant bits. >> >> > It also has a note it can't take all f's due to >> > an overflow from the conversion. >> >> Correct, because values between 0xfffffffffffffc00 and 2^64-1 round up >> to 2^64. > > Right, so these bother me not for normal sizes, but if we were to start > to use them for hex values with meanings, like addresses for example. > (Although I guess that's unlikely with the default assumption of MB)
Yes, 'o' is convenient in some cases, inconvenient in others, and incapable when you need more than 53 significant bits. >> If it bothers you, feel free to explore the following: feed the string >> both to strtod() and to strtoll(). Whichever eats more characters wins. > > Is the reason we're using strtod because we actively want users to be > able to say 3.5G ? I guess that's a reason to keep it. Early (and flawed) version(s) of the patch introducing strtosz() used strtoll(). Jes decided to switch to strtod() precisely to support things like 3.5G. >> This patch is of course just about better documenting what we have. I >> was starting to type something like "repeating the (complex) contract of >> qemu_strtosz_MiB() here isn't so hot, let's include it by reference >> instead", but then I looked it up. Pffft. >> >> > 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 guess the sanest solution is not to recognize suffixes when the number >> is hexadecimal. >> >> > (I also wouldn't bother expanding the size names and powers). >> >> I erred on the side of tedious clarity. Feel free to suggest something >> you like better. > > I think something like: > The optional suffix's b/k/m/g/t/p/e are accepted (upper or lower case) > to denote bytes, kibibytes, mebibytes etc. With no suffix, values > are interpreted as MiB. I like it. I'll fix "suffix's" to "suffixes", and list the suffixes in their "officially correct" case "b/k/M/G/T/P/E". >> >> + * >> >> + * 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. >> >> What I don't like about the previous description: it defines by example. >> Examples are great, but they are for illustrating a definition, they >> can't really replace one. > > I'm less fussy if it's clear; how about > '-' CHAR > True if optional single character argument (e.g. -f) is present > else absent. > > since you've got the '-' CHAR you have the definition. Sold. >> >> + * 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! >> >> Extra-special baroque! Took me a while to figure out WTF it does :) > > Should we avoid a lot of the 'o' pain by adding a new type; something > like: > '6' > A 64bit unsigned value. Decimal or hex integers are accepted; > optional suffixes of k/m/g/t/p/e are accepted to denote kibibytes > etc. With no suffix values are interpreted as bytes. > > then that would be suffix_mul() * qemu_strtou64() Feels like a good idea. Of course you need to find a few uses for it. Might even want to discourage new uses of 'o' then. > > Dave > >> >> */ >> >> >> >> typedef struct mon_cmd_t { >> >> -- >> >> 2.7.5 >> >> Thanks! > -- > Dr. David Alan Gilbert / dgilb...@redhat.com / Manchester, UK