diff options
Diffstat (limited to 'src/cmd/grep/main.c')
| -rw-r--r-- | src/cmd/grep/main.c | 260 |
1 files changed, 260 insertions, 0 deletions
diff --git a/src/cmd/grep/main.c b/src/cmd/grep/main.c new file mode 100644 index 00000000..f2a6e040 --- /dev/null +++ b/src/cmd/grep/main.c @@ -0,0 +1,260 @@ +#define EXTERN +#include "grep.h" + +char *validflags = "bchiLlnsv"; +void +usage(void) +{ + fprint(2, "usage: grep [-%s] [-f file] [-e expr] [file ...]\n", validflags); + exits("usage"); +} + +void +main(int argc, char *argv[]) +{ + int i, status; + + ARGBEGIN { + default: + if(utfrune(validflags, ARGC()) == nil) + usage(); + flags[ARGC()]++; + break; + + case 'e': + flags['e']++; + lineno = 0; + str2top(ARGF()); + break; + + case 'f': + flags['f']++; + filename = ARGF(); + rein = Bopen(filename, OREAD); + if(rein == 0) { + fprint(2, "grep: can't open %s: %r\n", filename); + exits("open"); + } + lineno = 1; + str2top(filename); + break; + } ARGEND + + if(flags['f'] == 0 && flags['e'] == 0) { + if(argc <= 0) + usage(); + str2top(argv[0]); + argc--; + argv++; + } + + follow = mal(maxfollow*sizeof(*follow)); + state0 = initstate(topre.beg); + + Binit(&bout, 1, OWRITE); + switch(argc) { + case 0: + status = search(0, 0); + break; + case 1: + status = search(argv[0], 0); + break; + default: + status = 0; + for(i=0; i<argc; i++) + status |= search(argv[i], Hflag); + break; + } + if(status) + exits(0); + exits("no matches"); +} + +int +search(char *file, int flag) +{ + State *s, *ns; + int c, fid, eof, nl, empty; + long count, lineno, n; + uchar *elp, *lp, *bol; + + if(file == 0) { + file = "stdin"; + fid = 0; + flag |= Bflag; + } else + fid = open(file, OREAD); + + if(fid < 0) { + fprint(2, "grep: can't open %s: %r\n", file); + return 0; + } + + if(flags['b']) + flag ^= Bflag; /* dont buffer output */ + if(flags['c']) + flag |= Cflag; /* count */ + if(flags['h']) + flag &= ~Hflag; /* do not print file name in output */ + if(flags['i']) + flag |= Iflag; /* fold upper-lower */ + if(flags['l']) + flag |= Llflag; /* print only name of file if any match */ + if(flags['L']) + flag |= LLflag; /* print only name of file if any non match */ + if(flags['n']) + flag |= Nflag; /* count only */ + if(flags['s']) + flag |= Sflag; /* status only */ + if(flags['v']) + flag |= Vflag; /* inverse match */ + + s = state0; + lineno = 0; + count = 0; + eof = 0; + empty = 1; + nl = 0; + lp = u.buf; + bol = lp; + +loop0: + n = lp-bol; + if(n > sizeof(u.pre)) + n = sizeof(u.pre); + memmove(u.buf-n, bol, n); + bol = u.buf-n; + n = read(fid, u.buf, sizeof(u.buf)); + /* if file has no final newline, simulate one to emit matches to last line */ + if(n > 0) { + empty = 0; + nl = u.buf[n-1]=='\n'; + } else { + if(n < 0){ + fprint(2, "grep: read error on %s: %r\n", file); + return count != 0; + } + if(!eof && !nl && !empty) { + u.buf[0] = '\n'; + n = 1; + eof = 1; + } + } + if(n <= 0) { + close(fid); + if(flag & Cflag) { + if(flag & Hflag) + Bprint(&bout, "%s:", file); + Bprint(&bout, "%ld\n", count); + } + if(((flag&Llflag) && count != 0) || ((flag&LLflag) && count == 0)) + Bprint(&bout, "%s\n", file); + Bflush(&bout); + return count != 0; + } + lp = u.buf; + elp = lp+n; + if(flag & Iflag) + goto loopi; + +/* + * normal character loop + */ +loop: + c = *lp; + ns = s->next[c]; + if(ns == 0) { + increment(s, c); + goto loop; + } +// if(flags['2']) +// if(s->match) +// print("%d: %.2x**\n", s, c); +// else +// print("%d: %.2x\n", s, c); + lp++; + s = ns; + if(c == '\n') { + lineno++; + if(!!s->match == !(flag&Vflag)) { + count++; + if(flag & (Cflag|Sflag|Llflag|LLflag)) + goto cont; + if(flag & Hflag) + Bprint(&bout, "%s:", file); + if(flag & Nflag) + Bprint(&bout, "%ld: ", lineno); + /* suppress extra newline at EOF unless we are labeling matches with file name */ + Bwrite(&bout, bol, lp-bol-(eof && !(flag&Hflag))); + if(flag & Bflag) + Bflush(&bout); + } + if((lineno & Flshcnt) == 0) + Bflush(&bout); + cont: + bol = lp; + } + if(lp != elp) + goto loop; + goto loop0; + +/* + * character loop for -i flag + * for speed + */ +loopi: + c = *lp; + if(c >= 'A' && c <= 'Z') + c += 'a'-'A'; + ns = s->next[c]; + if(ns == 0) { + increment(s, c); + goto loopi; + } + lp++; + s = ns; + if(c == '\n') { + lineno++; + if(!!s->match == !(flag&Vflag)) { + count++; + if(flag & (Cflag|Sflag|Llflag|LLflag)) + goto conti; + if(flag & Hflag) + Bprint(&bout, "%s:", file); + if(flag & Nflag) + Bprint(&bout, "%ld: ", lineno); + /* suppress extra newline at EOF unless we are labeling matches with file name */ + Bwrite(&bout, bol, lp-bol-(eof && !(flag&Hflag))); + if(flag & Bflag) + Bflush(&bout); + } + if((lineno & Flshcnt) == 0) + Bflush(&bout); + conti: + bol = lp; + } + if(lp != elp) + goto loopi; + goto loop0; +} + +State* +initstate(Re *r) +{ + State *s; + int i; + + addcase(r); + if(flags['1']) + reprint("r", r); + nfollow = 0; + gen++; + fol1(r, Cbegin); + follow[nfollow++] = r; + qsort(follow, nfollow, sizeof(*follow), fcmp); + + s = sal(nfollow); + for(i=0; i<nfollow; i++) + s->re[i] = follow[i]; + return s; +} |