ref: b502a62da2ec6058923db94f87ecc2d29db2fa77
dir: /os/port/parse.c/
#include "u.h" #include "../port/lib.h" #include "mem.h" #include "dat.h" #include "fns.h" #include "../port/error.h" /* * Generous estimate of number of fields, including terminal nil pointer */ static int ncmdfield(char *p, int n) { int white, nwhite; char *ep; int nf; if(p == nil) return 1; nf = 0; ep = p+n; white = 1; /* first text will start field */ while(p < ep){ nwhite = (strchr(" \t\r\n", *p++ & 0xFF) != 0); /* UTF is irrelevant */ if(white && !nwhite) /* beginning of field */ nf++; white = nwhite; } return nf+1; /* +1 for nil */ } /* * parse a command written to a device */ Cmdbuf* parsecmd(char *p, int n) { Cmdbuf *volatile cb; int nf; char *sp; nf = ncmdfield(p, n); /* allocate Cmdbuf plus string pointers plus copy of string including \0 */ sp = smalloc(sizeof(*cb) + nf * sizeof(char*) + n + 1); cb = (Cmdbuf*)sp; cb->f = (char**)(&cb[1]); cb->buf = (char*)(&cb->f[nf]); if(up!=nil && waserror()){ free(cb); nexterror(); } memmove(cb->buf, p, n); if(up != nil) poperror(); /* dump new line and null terminate */ if(n > 0 && cb->buf[n-1] == '\n') n--; cb->buf[n] = '\0'; cb->nf = tokenize(cb->buf, cb->f, nf-1); cb->f[cb->nf] = nil; return cb; } /* * Reconstruct original message, for error diagnostic */ void cmderror(Cmdbuf *cb, char *s) { int i; char *p, *e; p = up->genbuf; e = p+ERRMAX-10; p = seprint(p, e, "%s \"", s); for(i=0; i<cb->nf; i++){ if(i > 0) p = seprint(p, e, " "); p = seprint(p, e, "%q", cb->f[i]); } strcpy(p, "\""); error(up->genbuf); } /* * Look up entry in table */ Cmdtab* lookupcmd(Cmdbuf *cb, Cmdtab *ctab, int nctab) { int i; Cmdtab *ct; if(cb->nf == 0) error("empty control message"); for(ct = ctab, i=0; i<nctab; i++, ct++){ if(strcmp(ct->cmd, "*") !=0) /* wildcard always matches */ if(strcmp(ct->cmd, cb->f[0]) != 0) continue; if(ct->narg != 0 && ct->narg != cb->nf) cmderror(cb, Ecmdargs); return ct; } cmderror(cb, "unknown control message"); return nil; }