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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-10 21:30:40 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-10 21:30:40 +0000
commit133a45c109da5310add55824db21af5239951f93 (patch)
treeba6ac4c0a950a0dda56451944315d66409923918 /contrib/lua-lpeg/lpcap.c
parentInitial commit. (diff)
downloadrspamd-upstream.tar.xz
rspamd-upstream.zip
Adding upstream version 3.8.1.upstream/3.8.1upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to '')
-rw-r--r--contrib/lua-lpeg/lpcap.c555
1 files changed, 555 insertions, 0 deletions
diff --git a/contrib/lua-lpeg/lpcap.c b/contrib/lua-lpeg/lpcap.c
new file mode 100644
index 0000000..b332fde
--- /dev/null
+++ b/contrib/lua-lpeg/lpcap.c
@@ -0,0 +1,555 @@
+/*
+** $Id: lpcap.c $
+** Copyright 2007, Lua.org & PUC-Rio (see 'lpeg.html' for license)
+*/
+
+#include "lua.h"
+#include "lauxlib.h"
+
+#include "lpcap.h"
+#include "lptypes.h"
+
+
+#define captype(cap) ((cap)->kind)
+
+#define isclosecap(cap) (captype(cap) == Cclose)
+
+#define closeaddr(c) ((c)->s + (c)->siz - 1)
+
+#define isfullcap(cap) ((cap)->siz != 0)
+
+#define getfromktable(cs,v) lua_rawgeti((cs)->L, ktableidx((cs)->ptop), v)
+
+#define pushluaval(cs) getfromktable(cs, (cs)->cap->idx)
+
+
+
+/*
+** Put at the cache for Lua values the value indexed by 'v' in ktable
+** of the running pattern (if it is not there yet); returns its index.
+*/
+static int updatecache (CapState *cs, int v) {
+ int idx = cs->ptop + 1; /* stack index of cache for Lua values */
+ if (v != cs->valuecached) { /* not there? */
+ getfromktable(cs, v); /* get value from 'ktable' */
+ lua_replace(cs->L, idx); /* put it at reserved stack position */
+ cs->valuecached = v; /* keep track of what is there */
+ }
+ return idx;
+}
+
+
+static int pushcapture (CapState *cs);
+
+
+/*
+** Goes back in a list of captures looking for an open capture
+** corresponding to a close
+*/
+static Capture *findopen (Capture *cap) {
+ int n = 0; /* number of closes waiting an open */
+ for (;;) {
+ cap--;
+ if (isclosecap(cap)) n++; /* one more open to skip */
+ else if (!isfullcap(cap))
+ if (n-- == 0) return cap;
+ }
+}
+
+
+/*
+** Go to the next capture
+*/
+static void nextcap (CapState *cs) {
+ Capture *cap = cs->cap;
+ if (!isfullcap(cap)) { /* not a single capture? */
+ int n = 0; /* number of opens waiting a close */
+ for (;;) { /* look for corresponding close */
+ cap++;
+ if (isclosecap(cap)) {
+ if (n-- == 0) break;
+ }
+ else if (!isfullcap(cap)) n++;
+ }
+ }
+ cs->cap = cap + 1; /* + 1 to skip last close (or entire single capture) */
+}
+
+
+/*
+** Push on the Lua stack all values generated by nested captures inside
+** the current capture. Returns number of values pushed. 'addextra'
+** makes it push the entire match after all captured values. The
+** entire match is pushed also if there are no other nested values,
+** so the function never returns zero.
+*/
+static int pushnestedvalues (CapState *cs, int addextra) {
+ Capture *co = cs->cap;
+ if (isfullcap(cs->cap++)) { /* no nested captures? */
+ lua_pushlstring(cs->L, co->s, co->siz - 1); /* push whole match */
+ return 1; /* that is it */
+ }
+ else {
+ int n = 0;
+ while (!isclosecap(cs->cap)) /* repeat for all nested patterns */
+ n += pushcapture(cs);
+ if (addextra || n == 0) { /* need extra? */
+ lua_pushlstring(cs->L, co->s, cs->cap->s - co->s); /* push whole match */
+ n++;
+ }
+ cs->cap++; /* skip close entry */
+ return n;
+ }
+}
+
+
+/*
+** Push only the first value generated by nested captures
+*/
+static void pushonenestedvalue (CapState *cs) {
+ int n = pushnestedvalues(cs, 0);
+ if (n > 1)
+ lua_pop(cs->L, n - 1); /* pop extra values */
+}
+
+
+/*
+** Try to find a named group capture with the name given at the top of
+** the stack; goes backward from 'cap'.
+*/
+static Capture *findback (CapState *cs, Capture *cap) {
+ lua_State *L = cs->L;
+ while (cap-- > cs->ocap) { /* repeat until end of list */
+ if (isclosecap(cap))
+ cap = findopen(cap); /* skip nested captures */
+ else if (!isfullcap(cap))
+ continue; /* opening an enclosing capture: skip and get previous */
+ if (captype(cap) == Cgroup) {
+ getfromktable(cs, cap->idx); /* get group name */
+ if (lp_equal(L, -2, -1)) { /* right group? */
+ lua_pop(L, 2); /* remove reference name and group name */
+ return cap;
+ }
+ else lua_pop(L, 1); /* remove group name */
+ }
+ }
+ luaL_error(L, "back reference '%s' not found", lua_tostring(L, -1));
+ return NULL; /* to avoid warnings */
+}
+
+
+/*
+** Back-reference capture. Return number of values pushed.
+*/
+static int backrefcap (CapState *cs) {
+ int n;
+ Capture *curr = cs->cap;
+ pushluaval(cs); /* reference name */
+ cs->cap = findback(cs, curr); /* find corresponding group */
+ n = pushnestedvalues(cs, 0); /* push group's values */
+ cs->cap = curr + 1;
+ return n;
+}
+
+
+/*
+** Table capture: creates a new table and populates it with nested
+** captures.
+*/
+static int tablecap (CapState *cs) {
+ lua_State *L = cs->L;
+ int n = 0;
+ lua_newtable(L);
+ if (isfullcap(cs->cap++))
+ return 1; /* table is empty */
+ while (!isclosecap(cs->cap)) {
+ if (captype(cs->cap) == Cgroup && cs->cap->idx != 0) { /* named group? */
+ pushluaval(cs); /* push group name */
+ pushonenestedvalue(cs);
+ lua_settable(L, -3);
+ }
+ else { /* not a named group */
+ int i;
+ int k = pushcapture(cs);
+ for (i = k; i > 0; i--) /* store all values into table */
+ lua_rawseti(L, -(i + 1), n + i);
+ n += k;
+ }
+ }
+ cs->cap++; /* skip close entry */
+ return 1; /* number of values pushed (only the table) */
+}
+
+
+/*
+** Table-query capture
+*/
+static int querycap (CapState *cs) {
+ int idx = cs->cap->idx;
+ pushonenestedvalue(cs); /* get nested capture */
+ lua_gettable(cs->L, updatecache(cs, idx)); /* query cap. value at table */
+ if (!lua_isnil(cs->L, -1))
+ return 1;
+ else { /* no value */
+ lua_pop(cs->L, 1); /* remove nil */
+ return 0;
+ }
+}
+
+
+/*
+** Fold capture
+*/
+static int foldcap (CapState *cs) {
+ int n;
+ lua_State *L = cs->L;
+ int idx = cs->cap->idx;
+ if (isfullcap(cs->cap++) || /* no nested captures? */
+ isclosecap(cs->cap) || /* no nested captures (large subject)? */
+ (n = pushcapture(cs)) == 0) /* nested captures with no values? */
+ return luaL_error(L, "no initial value for fold capture");
+ if (n > 1)
+ lua_pop(L, n - 1); /* leave only one result for accumulator */
+ while (!isclosecap(cs->cap)) {
+ lua_pushvalue(L, updatecache(cs, idx)); /* get folding function */
+ lua_insert(L, -2); /* put it before accumulator */
+ n = pushcapture(cs); /* get next capture's values */
+ lua_call(L, n + 1, 1); /* call folding function */
+ }
+ cs->cap++; /* skip close entry */
+ return 1; /* only accumulator left on the stack */
+}
+
+
+/*
+** Function capture
+*/
+static int functioncap (CapState *cs) {
+ int n;
+ int top = lua_gettop(cs->L);
+ pushluaval(cs); /* push function */
+ n = pushnestedvalues(cs, 0); /* push nested captures */
+ lua_call(cs->L, n, LUA_MULTRET); /* call function */
+ return lua_gettop(cs->L) - top; /* return function's results */
+}
+
+
+/*
+** Select capture
+*/
+static int numcap (CapState *cs) {
+ int idx = cs->cap->idx; /* value to select */
+ if (idx == 0) { /* no values? */
+ nextcap(cs); /* skip entire capture */
+ return 0; /* no value produced */
+ }
+ else {
+ int n = pushnestedvalues(cs, 0);
+ if (n < idx) /* invalid index? */
+ return luaL_error(cs->L, "no capture '%d'", idx);
+ else {
+ lua_pushvalue(cs->L, -(n - idx + 1)); /* get selected capture */
+ lua_replace(cs->L, -(n + 1)); /* put it in place of 1st capture */
+ lua_pop(cs->L, n - 1); /* remove other captures */
+ return 1;
+ }
+ }
+}
+
+
+/*
+** Return the stack index of the first runtime capture in the given
+** list of captures (or zero if no runtime captures)
+*/
+int finddyncap (Capture *cap, Capture *last) {
+ for (; cap < last; cap++) {
+ if (cap->kind == Cruntime)
+ return cap->idx; /* stack position of first capture */
+ }
+ return 0; /* no dynamic captures in this segment */
+}
+
+
+/*
+** Calls a runtime capture. Returns number of captures "removed" by the
+** call, that is, those inside the group capture. Captures to be added
+** are on the Lua stack.
+*/
+int runtimecap (CapState *cs, Capture *close, const char *s, int *rem) {
+ int n, id;
+ lua_State *L = cs->L;
+ int otop = lua_gettop(L);
+ Capture *open = findopen(close); /* get open group capture */
+ assert(captype(open) == Cgroup);
+ id = finddyncap(open, close); /* get first dynamic capture argument */
+ close->kind = Cclose; /* closes the group */
+ close->s = s;
+ cs->cap = open; cs->valuecached = 0; /* prepare capture state */
+ luaL_checkstack(L, 4, "too many runtime captures");
+ pushluaval(cs); /* push function to be called */
+ lua_pushvalue(L, SUBJIDX); /* push original subject */
+ lua_pushinteger(L, s - cs->s + 1); /* push current position */
+ n = pushnestedvalues(cs, 0); /* push nested captures */
+ lua_call(L, n + 2, LUA_MULTRET); /* call dynamic function */
+ if (id > 0) { /* are there old dynamic captures to be removed? */
+ int i;
+ for (i = id; i <= otop; i++)
+ lua_remove(L, id); /* remove old dynamic captures */
+ *rem = otop - id + 1; /* total number of dynamic captures removed */
+ }
+ else
+ *rem = 0; /* no dynamic captures removed */
+ return close - open - 1; /* number of captures to be removed */
+}
+
+
+/*
+** Auxiliary structure for substitution and string captures: keep
+** information about nested captures for future use, avoiding to push
+** string results into Lua
+*/
+typedef struct StrAux {
+ int isstring; /* whether capture is a string */
+ union {
+ Capture *cp; /* if not a string, respective capture */
+ struct { /* if it is a string... */
+ const char *s; /* ... starts here */
+ const char *e; /* ... ends here */
+ } s;
+ } u;
+} StrAux;
+
+#define MAXSTRCAPS 10
+
+/*
+** Collect values from current capture into array 'cps'. Current
+** capture must be Cstring (first call) or Csimple (recursive calls).
+** (In first call, fills %0 with whole match for Cstring.)
+** Returns number of elements in the array that were filled.
+*/
+static int getstrcaps (CapState *cs, StrAux *cps, int n) {
+ int k = n++;
+ cps[k].isstring = 1; /* get string value */
+ cps[k].u.s.s = cs->cap->s; /* starts here */
+ if (!isfullcap(cs->cap++)) { /* nested captures? */
+ while (!isclosecap(cs->cap)) { /* traverse them */
+ if (n >= MAXSTRCAPS) /* too many captures? */
+ nextcap(cs); /* skip extra captures (will not need them) */
+ else if (captype(cs->cap) == Csimple) /* string? */
+ n = getstrcaps(cs, cps, n); /* put info. into array */
+ else {
+ cps[n].isstring = 0; /* not a string */
+ cps[n].u.cp = cs->cap; /* keep original capture */
+ nextcap(cs);
+ n++;
+ }
+ }
+ cs->cap++; /* skip close */
+ }
+ cps[k].u.s.e = closeaddr(cs->cap - 1); /* ends here */
+ return n;
+}
+
+
+/*
+** add next capture value (which should be a string) to buffer 'b'
+*/
+static int addonestring (luaL_Buffer *b, CapState *cs, const char *what);
+
+
+/*
+** String capture: add result to buffer 'b' (instead of pushing
+** it into the stack)
+*/
+static void stringcap (luaL_Buffer *b, CapState *cs) {
+ StrAux cps[MAXSTRCAPS];
+ int n;
+ size_t len, i;
+ const char *fmt; /* format string */
+ fmt = lua_tolstring(cs->L, updatecache(cs, cs->cap->idx), &len);
+ n = getstrcaps(cs, cps, 0) - 1; /* collect nested captures */
+ for (i = 0; i < len; i++) { /* traverse them */
+ if (fmt[i] != '%') /* not an escape? */
+ luaL_addchar(b, fmt[i]); /* add it to buffer */
+ else if (fmt[++i] < '0' || fmt[i] > '9') /* not followed by a digit? */
+ luaL_addchar(b, fmt[i]); /* add to buffer */
+ else {
+ int l = fmt[i] - '0'; /* capture index */
+ if (l > n)
+ luaL_error(cs->L, "invalid capture index (%d)", l);
+ else if (cps[l].isstring)
+ luaL_addlstring(b, cps[l].u.s.s, cps[l].u.s.e - cps[l].u.s.s);
+ else {
+ Capture *curr = cs->cap;
+ cs->cap = cps[l].u.cp; /* go back to evaluate that nested capture */
+ if (!addonestring(b, cs, "capture"))
+ luaL_error(cs->L, "no values in capture index %d", l);
+ cs->cap = curr; /* continue from where it stopped */
+ }
+ }
+ }
+}
+
+
+/*
+** Substitution capture: add result to buffer 'b'
+*/
+static void substcap (luaL_Buffer *b, CapState *cs) {
+ const char *curr = cs->cap->s;
+ if (isfullcap(cs->cap)) /* no nested captures? */
+ luaL_addlstring(b, curr, cs->cap->siz - 1); /* keep original text */
+ else {
+ cs->cap++; /* skip open entry */
+ while (!isclosecap(cs->cap)) { /* traverse nested captures */
+ const char *next = cs->cap->s;
+ luaL_addlstring(b, curr, next - curr); /* add text up to capture */
+ if (addonestring(b, cs, "replacement"))
+ curr = closeaddr(cs->cap - 1); /* continue after match */
+ else /* no capture value */
+ curr = next; /* keep original text in final result */
+ }
+ luaL_addlstring(b, curr, cs->cap->s - curr); /* add last piece of text */
+ }
+ cs->cap++; /* go to next capture */
+}
+
+
+/*
+** Evaluates a capture and adds its first value to buffer 'b'; returns
+** whether there was a value
+*/
+static int addonestring (luaL_Buffer *b, CapState *cs, const char *what) {
+ switch (captype(cs->cap)) {
+ case Cstring:
+ stringcap(b, cs); /* add capture directly to buffer */
+ return 1;
+ case Csubst:
+ substcap(b, cs); /* add capture directly to buffer */
+ return 1;
+ default: {
+ lua_State *L = cs->L;
+ int n = pushcapture(cs);
+ if (n > 0) {
+ if (n > 1) lua_pop(L, n - 1); /* only one result */
+ if (!lua_isstring(L, -1))
+ luaL_error(L, "invalid %s value (a %s)", what, luaL_typename(L, -1));
+ luaL_addvalue(b);
+ }
+ return n;
+ }
+ }
+}
+
+
+#if !defined(MAXRECLEVEL)
+#define MAXRECLEVEL 200
+#endif
+
+
+/*
+** Push all values of the current capture into the stack; returns
+** number of values pushed
+*/
+static int pushcapture (CapState *cs) {
+ lua_State *L = cs->L;
+ int res;
+ luaL_checkstack(L, 4, "too many captures");
+ if (cs->reclevel++ > MAXRECLEVEL)
+ return luaL_error(L, "subcapture nesting too deep");
+ switch (captype(cs->cap)) {
+ case Cposition: {
+ lua_pushinteger(L, cs->cap->s - cs->s + 1);
+ cs->cap++;
+ res = 1;
+ break;
+ }
+ case Cconst: {
+ pushluaval(cs);
+ cs->cap++;
+ res = 1;
+ break;
+ }
+ case Carg: {
+ int arg = (cs->cap++)->idx;
+ if (arg + FIXEDARGS > cs->ptop)
+ return luaL_error(L, "reference to absent extra argument #%d", arg);
+ lua_pushvalue(L, arg + FIXEDARGS);
+ res = 1;
+ break;
+ }
+ case Csimple: {
+ int k = pushnestedvalues(cs, 1);
+ lua_insert(L, -k); /* make whole match be first result */
+ res = k;
+ break;
+ }
+ case Cruntime: {
+ lua_pushvalue(L, (cs->cap++)->idx); /* value is in the stack */
+ res = 1;
+ break;
+ }
+ case Cstring: {
+ luaL_Buffer b;
+ luaL_buffinit(L, &b);
+ stringcap(&b, cs);
+ luaL_pushresult(&b);
+ res = 1;
+ break;
+ }
+ case Csubst: {
+ luaL_Buffer b;
+ luaL_buffinit(L, &b);
+ substcap(&b, cs);
+ luaL_pushresult(&b);
+ res = 1;
+ break;
+ }
+ case Cgroup: {
+ if (cs->cap->idx == 0) /* anonymous group? */
+ res = pushnestedvalues(cs, 0); /* add all nested values */
+ else { /* named group: add no values */
+ nextcap(cs); /* skip capture */
+ res = 0;
+ }
+ break;
+ }
+ case Cbackref: res = backrefcap(cs); break;
+ case Ctable: res = tablecap(cs); break;
+ case Cfunction: res = functioncap(cs); break;
+ case Cnum: res = numcap(cs); break;
+ case Cquery: res = querycap(cs); break;
+ case Cfold: res = foldcap(cs); break;
+ default: assert(0); res = 0;
+ }
+ cs->reclevel--;
+ return res;
+}
+
+
+/*
+** Prepare a CapState structure and traverse the entire list of
+** captures in the stack pushing its results. 's' is the subject
+** string, 'r' is the final position of the match, and 'ptop'
+** the index in the stack where some useful values were pushed.
+** Returns the number of results pushed. (If the list produces no
+** results, push the final position of the match.)
+*/
+int getcaptures (lua_State *L, const char *s, const char *r, int ptop) {
+ Capture *capture = (Capture *)lua_touserdata(L, caplistidx(ptop));
+ int n = 0;
+ if (!isclosecap(capture)) { /* is there any capture? */
+ CapState cs;
+ cs.ocap = cs.cap = capture; cs.L = L; cs.reclevel = 0;
+ cs.s = s; cs.valuecached = 0; cs.ptop = ptop;
+ do { /* collect their values */
+ n += pushcapture(&cs);
+ } while (!isclosecap(cs.cap));
+ }
+ if (n == 0) { /* no capture values? */
+ lua_pushinteger(L, r - s + 1); /* return only end position */
+ n = 1;
+ }
+ return n;
+}
+
+