ref: cd747191012d0420ac631340d962da1f80cef0a5
dir: /sys/src/cmd/mk/parse.c/
#include "mk.h" char *infile; int mkinline; static int rhead(char *, Word **, Word **, int *, char **); static char *rbody(Biobuf*); extern Word *target1; void parse(char *f, int fd, int varoverride) { int hline; char *body; Word *head, *tail; int attr, set, pid; char *prog, *p; int newfd; Biobuf in; Bufblock *buf; if(fd < 0){ perror(f); Exit(); } ipush(); infile = strdup(f); mkinline = 1; Binit(&in, fd, OREAD); buf = newbuf(); while(assline(&in, buf)){ hline = mkinline; switch(rhead(buf->start, &head, &tail, &attr, &prog)) { case '<': p = wtos(tail, ' '); if(*p == 0){ SYNERR(-1); fprint(2, "missing include file name\n"); Exit(); } newfd = open(p, OREAD); if(newfd < 0){ fprint(2, "warning: skipping missing include file: "); perror(p); } else parse(p, newfd, 0); break; case '|': p = wtos(tail, ' '); if(*p == 0){ SYNERR(-1); fprint(2, "missing include program name\n"); Exit(); } execinit(); pid=pipecmd(p, envy, &newfd); if(newfd < 0){ fprint(2, "warning: skipping missing program file: "); perror(p); } else parse(p, newfd, 0); while(waitup(-3, &pid) >= 0) ; if(pid != 0){ fprint(2, "bad include program status\n"); Exit(); } break; case ':': body = rbody(&in); addrules(head, tail, body, attr, hline, prog); break; case '=': if(head->next){ SYNERR(-1); fprint(2, "multiple vars on left side of assignment\n"); Exit(); } if(symlook(head->s, S_OVERRIDE, 0)){ set = varoverride; } else { set = 1; if(varoverride) symlook(head->s, S_OVERRIDE, (void *)""); } if(set){ /* char *cp; dumpw("tail", tail); cp = wtos(tail, ' '); print("assign %s to %s\n", head->s, cp); free(cp); */ setvar(head->s, (void *) tail); symlook(head->s, S_WESET, (void *)""); } if(attr) symlook(head->s, S_NOEXPORT, (void *)""); break; default: SYNERR(hline); fprint(2, "expected one of :<=\n"); Exit(); break; } } close(fd); freebuf(buf); ipop(); } void addrules(Word *head, Word *tail, char *body, int attr, int hline, char *prog) { Word *w; assert(/*addrules args*/ head && body); /* tuck away first non-meta rule as default target*/ if(target1 == 0 && !(attr®EXP)){ for(w = head; w; w = w->next) if(charin(w->s, "%&")) break; if(w == 0) target1 = wdup(head); } for(w = head; w; w = w->next) addrule(w->s, tail, body, head, attr, hline, prog); } static int rhead(char *line, Word **h, Word **t, int *attr, char **prog) { char *p; char *pp; int sep; Rune r; int n; Word *w; p = charin(line,":=<"); if(p == 0) return('?'); sep = *p; *p++ = 0; if(sep == '<' && *p == '|'){ sep = '|'; p++; } *attr = 0; *prog = 0; if(sep == '='){ pp = charin(p, termchars); /* termchars is shell-dependent */ if (pp && *pp == '=') { while (p != pp) { n = chartorune(&r, p); switch(r) { default: SYNERR(-1); fprint(2, "unknown attribute '%c'\n",*p); Exit(); case 'U': *attr = 1; break; } p += n; } p++; /* skip trailing '=' */ } } if((sep == ':') && *p && (*p != ' ') && (*p != '\t')){ while (*p) { n = chartorune(&r, p); if (r == ':') break; p += n; switch(r) { default: SYNERR(-1); fprint(2, "unknown attribute '%c'\n", p[-1]); Exit(); case 'D': *attr |= DEL; break; case 'E': *attr |= NOMINUSE; break; case 'n': *attr |= NOVIRT; break; case 'N': *attr |= NOREC; break; case 'P': pp = utfrune(p, ':'); if (pp == 0 || *pp == 0) goto eos; *pp = 0; *prog = strdup(p); *pp = ':'; p = pp; break; case 'Q': *attr |= QUIET; break; case 'R': *attr |= REGEXP; break; case 'U': *attr |= UPD; break; case 'V': *attr |= VIR; break; } } if (*p++ != ':') { eos: SYNERR(-1); fprint(2, "missing trailing :\n"); Exit(); } } *h = w = stow(line); if(*w->s == 0 && sep != '<' && sep != '|') { SYNERR(mkinline-1); fprint(2, "no var on left side of assignment/rule\n"); Exit(); } *t = stow(p); return(sep); } static char * rbody(Biobuf *in) { Bufblock *buf; int r, lastr; char *p; lastr = '\n'; buf = newbuf(); for(;;){ r = Bgetrune(in); if (r < 0) break; if (lastr == '\n') { if (r == '#') rinsert(buf, r); else if (r != ' ' && r != '\t') { Bungetrune(in); break; } } else rinsert(buf, r); lastr = r; if (r == '\n') mkinline++; } insert(buf, 0); p = strdup(buf->start); freebuf(buf); return p; } struct input { char *file; int line; struct input *next; }; static struct input *inputs = 0; void ipush(void) { struct input *in, *me; me = (struct input *)Malloc(sizeof(*me)); me->file = infile; me->line = mkinline; me->next = 0; if(inputs == 0) inputs = me; else { for(in = inputs; in->next; ) in = in->next; in->next = me; } } void ipop(void) { struct input *in, *me; assert(/*pop input list*/ inputs != 0); if(inputs->next == 0){ me = inputs; inputs = 0; } else { for(in = inputs; in->next->next; ) in = in->next; me = in->next; in->next = 0; } infile = me->file; mkinline = me->line; free((char *)me); }