Путь: Toys/POSIX, команды версии: Ver.4 Ver.9 grep Комментарии в файле grep.c :
Исходный текст в файле grep.c #define FOR_grep
#include "toys.h"
GLOBALS(
long m, A, B, C;
struct arg_list *f, *e, *M, *S, *exclude_dir;
char *color;
char *purple, *cyan, *red, *green, *grey;
struct double_list *reg;
int found, tried, delim;
struct arg_list *fixed[256];
)
struct reg {
struct reg *next, *prev;
int rc;
regex_t r;
regmatch_t m;
};
static void numdash(long num, char dash)
{
printf("%s%ld%s%c", TT.green, num, TT.cyan, dash);
}
// Emit line with various potential prefixes and delimiter
static void outline(char *line, char dash, char *name, long lcount, long bcount,
unsigned trim)
{
if (!trim && FLAG(o)) return;
if (name && FLAG(H)) printf("%s%s%s%c", TT.purple, name, TT.cyan, dash);
if (FLAG(c)) xprintf("%s%ld%c", TT.grey, lcount, TT.delim);
else if (lcount && FLAG(n)) numdash(lcount, dash);
if (bcount && FLAG(b)) numdash(bcount-1, dash);
if (line) {
if (FLAG(color)) xputsn(FLAG(o) ? TT.red : TT.grey);
// support embedded NUL bytes in output
xputsl(line, trim);
xputc(TT.delim);
}
}
// Show matches in one file
static void do_grep(int fd, char *name)
{
long lcount = 0, mcount = 0, offset = 0, after = 0, before = 0;
struct double_list *dlb = 0;
char *bars = 0;
FILE *file;
int bin = 0;
if (!FLAG(r)) TT.tried++;
if (!fd) name = "(standard input)";
// Only run binary file check on lseekable files.
if (!FLAG(a) && !lseek(fd, 0, SEEK_CUR)) {
char buf[256];
int len, i = 0;
unsigned wc;
// If the first 256 bytes don't parse as utf8, call it binary.
if (0<(len = read(fd, buf, 256))) {
lseek(fd, -len, SEEK_CUR);
while (i<len) {
bin = utf8towc(&wc, buf+i, len-i);
if (bin == -2) i = len;
if (bin<1) break;
i += bin;
}
bin = i!=len;
}
if (bin && FLAG(I)) return;
}
if (!(file = fdopen(fd, "r"))) return perror_msg("%s", name);
// Loop through lines of input
for (;;) {
char *line = 0, *start, *ss, *pp;
struct reg *shoe;
size_t ulen;
long len;
int matched = 0, rc = 1, move = 0, ii;
// get next line, check and trim delimiter
lcount++;
errno = 0;
ulen = len = getdelim(&line, &ulen, TT.delim, file);
if (len == -1 && errno) perror_msg("%s", name);
if (len<1) break;
if (line[ulen-1] == TT.delim) line[--ulen] = 0;
// Prepare for next line
start = line;
for (shoe = (void *)TT.reg; shoe; shoe = shoe->next) shoe->rc = 0;
// Loop to handle multiple matches in same line
do {
regmatch_t *mm = (void *)toybuf;
struct arg_list *seek;
mm->rm_so = mm->rm_eo = 0;
rc = 1;
// Handle "fixed" (literal) matches (if any)
if (TT.e && *start) for (ss = start; ss-line<ulen; ss++) {
ii = FLAG(i) ? toupper(*ss) : *ss;
for (seek = TT.fixed[ii]; seek; seek = seek->next) {
if (*(pp = seek->arg)=='^' && !FLAG(F)) {
if (ss!=start) continue;
pp++;
}
for (ii = 0; pp[ii] && ss[ii]; ii++) {
if (!FLAG(F)) {
if (pp[ii]=='.') continue;
if (pp[ii]=='\\' && pp[ii+1]) pp++;
else if (pp[ii]=='$' && !pp[ii+1]) break;
}
if (FLAG(i)) {
if (toupper(pp[ii])!=toupper(ss[ii])) break;
} else if (pp[ii]!=ss[ii]) break;
}
if (pp[ii] && (pp[ii]!='$' || pp[ii+1] || ss[ii])) continue;
mm->rm_eo = (mm->rm_so = ss-start)+ii;
rc = 0;
goto got;
}
if (FLAG(x)) break;
}
// Empty pattern always matches
if (rc && *TT.fixed && !FLAG(o)) rc = 0;
got:
// Handle regex matches (if any)
for (shoe = (void *)TT.reg; shoe; shoe = shoe->next) {
// Do we need to re-check this regex?
if (!shoe->rc) {
shoe->m.rm_so -= move;
shoe->m.rm_eo -= move;
if (!matched || shoe->m.rm_so<0)
shoe->rc = regexec0(&shoe->r, start, ulen-(start-line), 1,
&shoe->m, start==line ? 0 : REG_NOTBOL);
}
// If we got a match, is it a _better_ match?
if (!shoe->rc && (rc || shoe->m.rm_so < mm->rm_so ||
(shoe->m.rm_so == mm->rm_so && shoe->m.rm_eo >= mm->rm_eo)))
{
mm = &shoe->m;
rc = 0;
}
}
if (!rc && FLAG(o) && !mm->rm_eo && ulen>start-line) {
move = 1;
continue;
}
if (!rc && FLAG(x) && (mm->rm_so || ulen-(start-line)!=mm->rm_eo)) rc = 1;
if (!rc && FLAG(w)) {
char c = 0;
if ((start+mm->rm_so)!=line) {
c = start[mm->rm_so-1];
if (!isalnum(c) && c != '_') c = 0;
}
if (!c) {
c = start[mm->rm_eo];
if (!isalnum(c) && c != '_') c = 0;
}
if (c) {
move = mm->rm_so+1;
continue;
}
}
if (FLAG(v)) {
if (FLAG(o)) {
if (rc) mm->rm_eo = ulen-(start-line);
else if (!mm->rm_so) {
move = mm->rm_eo;
continue;
} else mm->rm_eo = mm->rm_so;
} else {
if (!rc) break;
mm->rm_eo = ulen-(start-line);
}
mm->rm_so = 0;
} else if (rc) break;
// At least one line we didn't print since match while -ABC active
if (bars) {
xputs(bars);
bars = 0;
}
matched++;
TT.found = 1;
// Are we NOT showing the matching text?
if (FLAG(q)) {
toys.exitval = 0;
xexit();
}
if (FLAG(L) || FLAG(l)) {
if (FLAG(l)) xprintf("%s%c", name, '\n'*!FLAG(Z));
free(line);
fclose(file);
return;
}
if (!FLAG(c)) {
long bcount = 1 + offset + (start-line) + (FLAG(o) ? mm->rm_so : 0);
if (bin) printf("Binary file %s matches\n", name);
else if (FLAG(o))
outline(start+mm->rm_so, ':', name, lcount, bcount,
mm->rm_eo-mm->rm_so);
else {
while (dlb) {
struct double_list *dl = dlist_pop(&dlb);
unsigned *uu = (void *)(dl->data+(strlen(dl->data)|3)+1);
outline(dl->data, '-', name, lcount-before, uu[0]+1, uu[1]);
free(dl->data);
free(dl);
before--;
}
if (matched==1)
outline(FLAG(color) ? 0 : line, ':', name, lcount, bcount, ulen);
if (FLAG(color)) {
xputsn(TT.grey);
if (mm->rm_so) xputsl(start, mm->rm_so);
xputsn(TT.red);
xputsl(start+mm->rm_so, mm->rm_eo-mm->rm_so);
}
if (TT.A) after = TT.A+1;
}
}
if (mm->rm_so == (move = mm->rm_eo)) break;
} while (*(start += move));
offset += len;
if (matched) {
// Finish off pending line color fragment.
if (FLAG(color) && !FLAG(o)) {
xputsn(TT.grey);
if (ulen > start-line) xputsl(start, ulen-(start-line));
xputc(TT.delim);
}
mcount++;
} else {
int discard = (after || TT.B);
if (after && --after) {
outline(line, '-', name, lcount, 0, ulen);
discard = 0;
}
if (discard && TT.B) {
unsigned *uu, ul = (ulen|3)+1;
line = xrealloc(line, ul+8);
uu = (void *)(line+ul);
uu[0] = offset-len;
uu[1] = ulen;
dlist_add(&dlb, line);
line = 0;
if (++before>TT.B) {
struct double_list *dl;
dl = dlist_pop(&dlb);
free(dl->data);
free(dl);
before--;
} else discard = 0;
}
// If we discarded a line while displaying context, show bars before next
// line (but don't show them now in case that was last match in file)
if (discard && mcount) bars = "--";
}
free(line);
if (FLAG(m) && mcount >= TT.m) break;
}
if (FLAG(L)) xprintf("%s%c", name, TT.delim);
else if (FLAG(c)) outline(0, ':', name, mcount, 0, 1);
// loopfiles will also close the fd, but this frees an (opaque) struct.
fclose(file);
while (dlb) {
struct double_list *dl = dlist_pop(&dlb);
free(dl->data);
free(dl);
}
}
static int lensort(struct arg_list **a, struct arg_list **b)
{
long la = strlen((*a)->arg), lb = strlen((*b)->arg);
if (la<lb) return -1;
if (la>lb) return 1;
return 0;
}
static void parse_regex(void)
{
struct arg_list *al, *new, *list = NULL, **last;
char *s, *ss, *special = "\\.^$[()|*+?{";
int len, ii, key;
// Add all -f lines to -e list. (Yes, this is leaking allocation context for
// exit to free. Not supporting nofork for this command any time soon.)
al = TT.f ? TT.f : TT.e;
while (al) {
if (TT.f) {
if (!*(s = xreadfile(al->arg, 0, 0))) {
free(s);
s = 0;
} else if (*(ss = s+strlen(s)-1)=='\n') *ss = 0;
} else s = al->arg;
// Advance, when we run out of -f switch to -e.
al = al->next;
if (!al && TT.f) {
TT.f = 0;
al = TT.e;
}
if (!s) continue;
// NOTE: even with -z, -f is still \n delimited. Blank line = match all
// Split lines at \n, add individual lines to new list.
do {
if ((ss = strchr(s, '\n'))) *(ss++) = 0;
new = xmalloc(sizeof(struct arg_list));
new->next = list;
new->arg = s;
list = new;
s = ss;
} while (s);
}
TT.e = list;
// Convert to regex where appropriate
for (last = &TT.e; *last;) {
// Can we use the fast path?
s = (*last)->arg;
if ('.'!=*s && !FLAG(F) && strcmp(s, "^$")) for (; *s; s++) {
if (*s=='\\') {
if (!s[1] || !strchr(special, *++s)) break;
if (!FLAG(E) && *s=='(') break;
} else if (*s>127 || strchr(special+4, *s)) break;
}
// Add entry to fast path (literal-ish match) or slow path (regexec)
if (!*s || FLAG(F)) last = &((*last)->next);
else {
struct reg *shoe;
dlist_add_nomalloc(&TT.reg, (void *)(shoe = xmalloc(sizeof(struct reg))));
xregcomp(&shoe->r, (*last)->arg,
(REG_EXTENDED*!!FLAG(E))|(REG_ICASE*!!FLAG(i)));
al = *last;
*last = (*last)->next;
free(al);
}
}
dlist_terminate(TT.reg);
// Sort fast path patterns into buckets by first character
for (al = TT.e; al; al = new) {
new = al->next;
if (FLAG(F)) key = 0;
else {
key = '^'==*al->arg;
if ('\\'==al->arg[key]) key++;
else if ('$'==al->arg[key] && !al->arg[key+1]) key++;
}
key = al->arg[key];
if (FLAG(i)) key = toupper(key);
al->next = TT.fixed[key];
TT.fixed[key] = al;
}
// Sort each fast path pattern set by length so first hit is longest match
if (TT.e) for (key = 0; key<256; key++) {
if (!TT.fixed[key]) continue;
for (len = 0, al = TT.fixed[key]; al; al = al->next) len++;
last = xmalloc(len*sizeof(void *));
for (len = 0, al = TT.fixed[key]; al; al = al->next) last[len++] = al;
qsort(last, len, sizeof(void *), (void *)lensort);
for (ii = 0; ii<len; ii++) last[ii]->next = ii ? last[ii-1] : 0;
TT.fixed[key] = last[len-1];
free(last);
}
}
static int do_grep_r(struct dirtree *new)
{
struct arg_list *al;
char *name;
if (!new->parent) TT.tried++;
if (!dirtree_notdotdot(new)) return 0;
if (S_ISDIR(new->st.st_mode)) {
for (al = TT.exclude_dir; al; al = al->next)
if (!fnmatch(al->arg, new->name, 0)) return 0;
return DIRTREE_RECURSE|(FLAG(R)?DIRTREE_SYMFOLLOW:0);
}
if (TT.S || TT.M) {
for (al = TT.S; al; al = al->next)
if (!fnmatch(al->arg, new->name, 0)) return 0;
if (TT.M) {
for (al = TT.M; al; al = al->next)
if (!fnmatch(al->arg, new->name, 0)) break;
if (!al) return 0;
}
}
// "grep -r onefile" doesn't show filenames, but "grep -r onedir" should.
if (new->parent && !FLAG(h)) toys.optflags |= FLAG_H;
name = dirtree_path(new, 0);
do_grep(openat(dirtree_parentfd(new), new->name, 0), name);
free(name);
return 0;
}
void grep_main(void)
{
char **ss = toys.optargs;
if (FLAG(color) && (!TT.color || !strcmp(TT.color, "auto")) && !isatty(1))
toys.optflags &= ~FLAG_color;
if (FLAG(color)) {
TT.purple = "\e[35m";
TT.cyan = "\e[36m";
TT.red = "\e[1;31m";
TT.green = "\e[32m";
TT.grey = "\e[m";
} else TT.purple = TT.cyan = TT.red = TT.green = TT.grey = "";
if (FLAG(R)) toys.optflags |= FLAG_r;
// Grep exits with 2 for errors
toys.exitval = 2;
if (!TT.A) TT.A = TT.C;
if (!TT.B) TT.B = TT.C;
TT.delim = '\n' * !FLAG(z);
// Handle egrep and fgrep
if (*toys.which->name == 'e') toys.optflags |= FLAG_E;
if (*toys.which->name == 'f') toys.optflags |= FLAG_F;
if (!TT.e && !TT.f) {
if (!*ss) error_exit("no REGEX");
TT.e = xzalloc(sizeof(struct arg_list));
TT.e->arg = *(ss++);
toys.optc--;
}
parse_regex();
if (!FLAG(h) && toys.optc>1) toys.optflags |= FLAG_H;
if (FLAG(s)) {
close(2);
xopen_stdio("/dev/null", O_RDWR);
}
if (FLAG(r)) {
// Iterate through -r arguments. Use "." as default if none provided.
for (ss = *ss ? ss : (char *[]){".", 0}; *ss; ss++) {
if (!strcmp(*ss, "-")) do_grep(0, *ss);
else dirtree_read(*ss, do_grep_r);
}
} else loopfiles_rw(ss, O_RDONLY|WARN_ONLY, 0, do_grep);
if (TT.tried >= toys.optc || (FLAG(q)&&TT.found)) toys.exitval = !TT.found;
} |
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