PARSECMD 10.2
NAME
parsecmd - parse device commands
SYNOPSIS
Cmdbuf* parsecmd(char *a, int n)
DESCRIPTION
Parsecmd is an interface to
tokenize (see
getfields (10.2)), that safely parses a command, with blank-separated fields, as might be
written to a device's
ctl file.
The buffer
a and count
n can be those passed to the driver's
write function.
Parsecmd converts the byte array (which might not be null-terminated) to a null-terminated string,
trimming any trailing new line,
before invoking
tokenize to break the string into arguments, interpreting blank and tab as field separators
when they are not quoted
(in the style of
sh (1)). It returns a pointer to a dynamically-allocated
Cmdbuf structure,
which holds a copy of the string as
modified by
parsefields , and the resulting fields; it is defined as follows:
.EX
typedef
struct Cmdbuf
{
char buf[128];
char *f[16];
int nf;
} Cmdbuf;
The array f holds the field pointers; nf gives the number of fields. Cmdbuf is allocated by smalloc (see malloc (10.2)), and the caller is responsible for freeing it using free .
SOURCE
/os/port/parse.c