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Diffstat (limited to 'vm.c')
-rw-r--r--vm.c176
1 files changed, 88 insertions, 88 deletions
diff --git a/vm.c b/vm.c
index bddd9d2..b54f08d 100644
--- a/vm.c
+++ b/vm.c
@@ -123,7 +123,7 @@ static const char *match_backref(const char *str, match_t *cap, unsigned int ign
//
// Find the next match after prev (or the first match if prev is NULL)
//
-match_t *next_match(def_t *defs, file_t *f, match_t *prev, pat_t *op, unsigned int ignorecase)
+match_t *next_match(def_t *defs, file_t *f, match_t *prev, pat_t *pat, unsigned int ignorecase)
{
const char *str;
if (prev) {
@@ -133,71 +133,71 @@ match_t *next_match(def_t *defs, file_t *f, match_t *prev, pat_t *op, unsigned i
str = f->contents;
}
for (; str < f->end; ++str) {
- match_t *m = match(defs, f, str, op, ignorecase);
+ match_t *m = match(defs, f, str, pat, ignorecase);
if (m) return m;
}
return NULL;
}
//
-// Run virtual machine operation against a string and return
-// a match struct, or NULL if no match is found.
+// Attempt to match the given pattern against the input string and return a
+// match object, or NULL if no match is found.
// The returned value should be free()'d to avoid memory leaking.
//
-match_t *match(def_t *defs, file_t *f, const char *str, pat_t *op, unsigned int ignorecase)
+match_t *match(def_t *defs, file_t *f, const char *str, pat_t *pat, unsigned int ignorecase)
{
- switch (op->type) {
+ switch (pat->type) {
case VM_LEFTRECURSION: {
// Left recursion occurs when a pattern directly or indirectly
// invokes itself at the same position in the text. It's handled as
// a special case, but if a pattern invokes itself at a later
// point, it can be handled with normal recursion.
// See: left-recursion.md for more details.
- if (str == op->args.leftrec.at) {
- ++op->args.leftrec.visits;
- return op->args.leftrec.match;
+ if (str == pat->args.leftrec.at) {
+ ++pat->args.leftrec.visits;
+ return pat->args.leftrec.match;
} else {
- return match(defs, f, str, op->args.leftrec.fallback, ignorecase);
+ return match(defs, f, str, pat->args.leftrec.fallback, ignorecase);
}
}
case VM_ANYCHAR: {
if (str >= f->end || *str == '\n')
return NULL;
match_t *m = new_match();
- m->pat = op;
+ m->pat = pat;
m->start = str;
m->end = next_char(f, str);
return m;
}
case VM_STRING: {
- if (&str[op->len] > f->end) return NULL;
- if (ignorecase ? memicmp(str, op->args.s, (size_t)op->len) != 0
- : memcmp(str, op->args.s, (size_t)op->len) != 0)
+ if (&str[pat->len] > f->end) return NULL;
+ if (ignorecase ? memicmp(str, pat->args.s, (size_t)pat->len) != 0
+ : memcmp(str, pat->args.s, (size_t)pat->len) != 0)
return NULL;
match_t *m = new_match();
- m->pat = op;
+ m->pat = pat;
m->start = str;
- m->end = str + op->len;
+ m->end = str + pat->len;
return m;
}
case VM_RANGE: {
if (str >= f->end) return NULL;
- if ((unsigned char)*str < op->args.range.low || (unsigned char)*str > op->args.range.high)
+ if ((unsigned char)*str < pat->args.range.low || (unsigned char)*str > pat->args.range.high)
return NULL;
match_t *m = new_match();
- m->pat = op;
+ m->pat = pat;
m->start = str;
m->end = str + 1;
return m;
}
case VM_NOT: {
- match_t *m = match(defs, f, str, op->args.pat, ignorecase);
+ match_t *m = match(defs, f, str, pat->args.pat, ignorecase);
if (m != NULL) {
recycle_if_unused(&m);
return NULL;
}
m = new_match();
- m->pat = op;
+ m->pat = pat;
m->start = str;
m->end = str;
return m;
@@ -205,10 +205,10 @@ match_t *match(def_t *defs, file_t *f, const char *str, pat_t *op, unsigned int
case VM_UPTO_AND: {
match_t *m = new_match();
m->start = str;
- m->pat = op;
+ m->pat = pat;
- pat_t *pat = op->args.multiple.first, *skip = op->args.multiple.second;
- if (!pat && !skip) {
+ pat_t *target = pat->args.multiple.first, *skip = pat->args.multiple.second;
+ if (!target && !skip) {
while (str < f->end && *str != '\n') ++str;
m->end = str;
return m;
@@ -217,8 +217,8 @@ match_t *match(def_t *defs, file_t *f, const char *str, pat_t *op, unsigned int
match_t **dest = &m->child;
for (const char *prev = NULL; prev < str; ) {
prev = str;
- if (pat) {
- match_t *p = match(defs, f, str, pat, ignorecase);
+ if (target) {
+ match_t *p = match(defs, f, str, target, ignorecase);
if (p != NULL) {
ADD_OWNER(*dest, p);
m->end = p->end;
@@ -250,51 +250,51 @@ match_t *match(def_t *defs, file_t *f, const char *str, pat_t *op, unsigned int
match_t *m = new_match();
m->start = str;
m->end = str;
- m->pat = op;
+ m->pat = pat;
match_t **dest = &m->child;
size_t reps = 0;
- ssize_t max = op->args.repetitions.max;
+ ssize_t max = pat->args.repetitions.max;
for (reps = 0; max == -1 || reps < (size_t)max; ++reps) {
const char *start = str;
// Separator
- match_t *sep = NULL;
- if (op->args.repetitions.sep != NULL && reps > 0) {
- sep = match(defs, f, str, op->args.repetitions.sep, ignorecase);
- if (sep == NULL) break;
- str = sep->end;
+ match_t *msep = NULL;
+ if (pat->args.repetitions.sep != NULL && reps > 0) {
+ msep = match(defs, f, str, pat->args.repetitions.sep, ignorecase);
+ if (msep == NULL) break;
+ str = msep->end;
}
- match_t *p = match(defs, f, str, op->args.repetitions.repeat_pat, ignorecase);
- if (p == NULL) {
+ match_t *mp = match(defs, f, str, pat->args.repetitions.repeat_pat, ignorecase);
+ if (mp == NULL) {
str = start;
- recycle_if_unused(&sep);
+ recycle_if_unused(&msep);
break;
}
- if (p->end == start && reps > 0) {
- // Since no forward progress was made on either `pat` or
- // `sep` and BP does not have mutable state, it's
- // guaranteed that no progress will be made on the next
- // loop either. We know that this will continue to loop
- // until reps==max, so let's just cut to the chase instead
- // of looping infinitely.
- recycle_if_unused(&sep);
- recycle_if_unused(&p);
- if (op->args.repetitions.max == -1)
+ if (mp->end == start && reps > 0) {
+ // Since no forward progress was made on either
+ // `repeat_pat` or `sep` and BP does not have mutable
+ // state, it's guaranteed that no progress will be made on
+ // the next loop either. We know that this will continue to
+ // loop until reps==max, so let's just cut to the chase
+ // instead of looping infinitely.
+ recycle_if_unused(&msep);
+ recycle_if_unused(&mp);
+ if (pat->args.repetitions.max == -1)
reps = ~(size_t)0;
else
- reps = (size_t)op->args.repetitions.max;
+ reps = (size_t)pat->args.repetitions.max;
break;
}
- if (sep) {
- ADD_OWNER(*dest, sep);
- dest = &sep->nextsibling;
+ if (msep) {
+ ADD_OWNER(*dest, msep);
+ dest = &msep->nextsibling;
}
- ADD_OWNER(*dest, p);
- dest = &p->nextsibling;
- str = p->end;
+ ADD_OWNER(*dest, mp);
+ dest = &mp->nextsibling;
+ str = mp->end;
}
- if (reps < (size_t)op->args.repetitions.min) {
+ if (reps < (size_t)pat->args.repetitions.min) {
recycle_if_unused(&m);
return NULL;
}
@@ -302,45 +302,45 @@ match_t *match(def_t *defs, file_t *f, const char *str, pat_t *op, unsigned int
return m;
}
case VM_AFTER: {
- ssize_t backtrack = op->args.pat->len;
+ ssize_t backtrack = pat->args.pat->len;
check(backtrack != -1, "'<' is only allowed for fixed-length operations");
if (str - backtrack < f->contents) return NULL;
- match_t *before = match(defs, f, str - backtrack, op->args.pat, ignorecase);
+ match_t *before = match(defs, f, str - backtrack, pat->args.pat, ignorecase);
if (before == NULL) return NULL;
match_t *m = new_match();
m->start = str;
m->end = str;
- m->pat = op;
+ m->pat = pat;
ADD_OWNER(m->child, before);
return m;
}
case VM_BEFORE: {
- match_t *after = match(defs, f, str, op->args.pat, ignorecase);
+ match_t *after = match(defs, f, str, pat->args.pat, ignorecase);
if (after == NULL) return NULL;
match_t *m = new_match();
m->start = str;
m->end = str;
- m->pat = op;
+ m->pat = pat;
ADD_OWNER(m->child, after);
return m;
}
case VM_CAPTURE: {
- match_t *p = match(defs, f, str, op->args.pat, ignorecase);
+ match_t *p = match(defs, f, str, pat->args.pat, ignorecase);
if (p == NULL) return NULL;
match_t *m = new_match();
m->start = str;
m->end = p->end;
- m->pat = op;
+ m->pat = pat;
ADD_OWNER(m->child, p);
return m;
}
case VM_OTHERWISE: {
- match_t *m = match(defs, f, str, op->args.multiple.first, ignorecase);
- if (m == NULL) m = match(defs, f, str, op->args.multiple.second, ignorecase);
+ match_t *m = match(defs, f, str, pat->args.multiple.first, ignorecase);
+ if (m == NULL) m = match(defs, f, str, pat->args.multiple.second, ignorecase);
return m;
}
case VM_CHAIN: {
- match_t *m1 = match(defs, f, str, op->args.multiple.first, ignorecase);
+ match_t *m1 = match(defs, f, str, pat->args.multiple.first, ignorecase);
if (m1 == NULL) return NULL;
match_t *m2;
@@ -349,7 +349,7 @@ match_t *match(def_t *defs, file_t *f, const char *str, pat_t *op, unsigned int
if (m1->pat->type == VM_CAPTURE && m1->pat->args.capture.name)
defs2 = with_backref(defs2, f, m1->pat->args.capture.name, m1);
// def_t *defs2 = with_backrefs(defs, f, m1);
- m2 = match(defs2, f, m1->end, op->args.multiple.second, ignorecase);
+ m2 = match(defs2, f, m1->end, pat->args.multiple.second, ignorecase);
free_defs(&defs2, defs);
}
@@ -360,13 +360,13 @@ match_t *match(def_t *defs, file_t *f, const char *str, pat_t *op, unsigned int
match_t *m = new_match();
m->start = str;
m->end = m2->end;
- m->pat = op;
+ m->pat = pat;
ADD_OWNER(m->child, m1);
ADD_OWNER(m1->nextsibling, m2);
return m;
}
case VM_EQUAL: case VM_NOT_EQUAL: {
- match_t *m1 = match(defs, f, str, op->args.multiple.first, ignorecase);
+ match_t *m1 = match(defs, f, str, pat->args.multiple.first, ignorecase);
if (m1 == NULL) return NULL;
// <p1>==<p2> matches iff the text of <p1> matches <p2>
@@ -378,8 +378,8 @@ match_t *match(def_t *defs, file_t *f, const char *str, pat_t *op, unsigned int
.nlines=1 + get_line_number(f, m1->end)-get_line_number(f, m1->start),
.mmapped=f->mmapped,
};
- match_t *m2 = match(defs, &inner, str, op->args.multiple.second, ignorecase);
- if ((m2 == NULL) == (op->type == VM_EQUAL)) {
+ match_t *m2 = match(defs, &inner, str, pat->args.multiple.second, ignorecase);
+ if ((m2 == NULL) == (pat->type == VM_EQUAL)) {
recycle_if_unused(&m1);
if (m2 != NULL) recycle_if_unused(&m2);
return NULL;
@@ -387,9 +387,9 @@ match_t *match(def_t *defs, file_t *f, const char *str, pat_t *op, unsigned int
match_t *m = new_match();
m->start = m1->start;
m->end = m1->end;
- m->pat = op;
+ m->pat = pat;
ADD_OWNER(m->child, m1);
- if (op->type == VM_EQUAL) {
+ if (pat->type == VM_EQUAL) {
ADD_OWNER(m1->nextsibling, m2);
} else {
recycle_if_unused(&m2);
@@ -398,13 +398,13 @@ match_t *match(def_t *defs, file_t *f, const char *str, pat_t *op, unsigned int
}
case VM_REPLACE: {
match_t *p = NULL;
- if (op->args.replace.pat) {
- p = match(defs, f, str, op->args.replace.pat, ignorecase);
+ if (pat->args.replace.pat) {
+ p = match(defs, f, str, pat->args.replace.pat, ignorecase);
if (p == NULL) return NULL;
}
match_t *m = new_match();
m->start = str;
- m->pat = op;
+ m->pat = pat;
if (p) {
ADD_OWNER(m->child, p);
m->end = p->end;
@@ -414,8 +414,8 @@ match_t *match(def_t *defs, file_t *f, const char *str, pat_t *op, unsigned int
return m;
}
case VM_REF: {
- def_t *def = lookup(defs, op->args.s);
- check(def != NULL, "Unknown identifier: '%s'", op->args.s);
+ def_t *def = lookup(defs, pat->args.s);
+ check(def != NULL, "Unknown identifier: '%s'", pat->args.s);
pat_t *ref = def->pat;
pat_t rec_op = {
@@ -470,17 +470,17 @@ match_t *match(def_t *defs, file_t *f, const char *str, pat_t *op, unsigned int
// match results.
// OPTIMIZE: remove this if necessary
match_t *m2 = new_match();
- m2->pat = op;
+ m2->pat = pat;
m2->start = m->start;
m2->end = m->end;
ADD_OWNER(m2->child, m);
return m2;
}
case VM_BACKREF: {
- const char *end = match_backref(str, op->args.backref, ignorecase);
+ const char *end = match_backref(str, pat->args.backref, ignorecase);
if (end == NULL) return NULL;
match_t *m = new_match();
- m->pat = op;
+ m->pat = pat;
m->start = str;
m->end = end;
return m;
@@ -509,11 +509,11 @@ match_t *match(def_t *defs, file_t *f, const char *str, pat_t *op, unsigned int
match_t *m = new_match();
m->start = start;
m->end = &str[dents];
- m->pat = op;
+ m->pat = pat;
return m;
}
default: {
- fprintf(stderr, "Unknown pattern type: %d", op->type);
+ fprintf(stderr, "Unknown pattern type: %d", pat->type);
exit(1);
return NULL;
}
@@ -665,21 +665,21 @@ size_t free_all_matches(void)
#endif
//
-// Deallocate memory associated with an op
+// Deallocate memory referenced inside a pattern struct
//
-void destroy_pat(pat_t *op)
+void destroy_pat(pat_t *pat)
{
- switch (op->type) {
+ switch (pat->type) {
case VM_STRING: case VM_REF:
- xfree(&op->args.s);
+ xfree(&pat->args.s);
break;
case VM_CAPTURE:
- if (op->args.capture.name)
- xfree(&op->args.capture.name);
+ if (pat->args.capture.name)
+ xfree(&pat->args.capture.name);
break;
case VM_REPLACE:
- if (op->args.replace.text)
- xfree(&op->args.replace.text);
+ if (pat->args.replace.text)
+ xfree(&pat->args.replace.text);
break;
default: break;
}
generated by cgit v1.2.3 (git 2.25.1) at 2026-03-01 13:13:51 +0000