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/* -*- Mode: C; tab-width: 4; c-basic-offset: 4; indent-tabs-mode: nil -*- */
#include "proxy.h"
// mcp.add_stat(index, name)
// creates a custom lua stats counter
int mcplib_add_stat(lua_State *L) {
int idx = luaL_checkinteger(L, -2);
const char *name = luaL_checkstring(L, -1);
if (idx < 1) {
proxy_lua_error(L, "stat index must be 1 or higher");
return 0;
}
// max user counters? 1024? some weird number.
if (idx > 1024) {
proxy_lua_error(L, "stat index must be 1024 or less");
return 0;
}
// max name length? avoids errors if something huge gets thrown in.
if (strlen(name) > STAT_KEY_LEN - 6) {
// we prepend "user_" to the output. + null byte.
proxy_lua_ferror(L, "stat name too long: %s\n", name);
return 0;
}
// restrict characters, at least no spaces/newlines.
for (int x = 0; x < strlen(name); x++) {
if (isspace(name[x])) {
proxy_lua_error(L, "stat cannot contain spaces or newlines");
return 0;
}
}
proxy_ctx_t *ctx = PROXY_GET_CTX(L);
STAT_L(ctx);
struct proxy_user_stats *us = &ctx->user_stats;
// if num_stats is 0 we need to init sizes.
// TODO (v2): malloc fail checking. (should be rare/impossible)
if (us->num_stats < idx) {
// don't allocate counters memory for the global ctx.
char **nnames = calloc(idx, sizeof(char *));
if (us->names != NULL) {
for (int x = 0; x < us->num_stats; x++) {
nnames[x] = us->names[x];
}
free(us->names);
}
us->names = nnames;
us->num_stats = idx;
}
idx--; // real slot start as 0.
// if slot has string in it, free first
if (us->names[idx] != NULL) {
free(us->names[idx]);
}
// strdup name into string slot
// TODO (v2): malloc failure.
us->names[idx] = strdup(name);
STAT_UL(ctx);
return 0;
}
int mcplib_stat(lua_State *L) {
LIBEVENT_THREAD *t = PROXY_GET_THR(L);
if (t == NULL) {
proxy_lua_error(L, "stat must be called from router handlers");
return 0;
}
struct proxy_user_stats *tus = t->proxy_user_stats;
if (tus == NULL) {
proxy_lua_error(L, "no stats counters initialized");
return 0;
}
int idx = luaL_checkinteger(L, -2);
int change = luaL_checkinteger(L, -1);
if (idx < 1 || idx > tus->num_stats) {
proxy_lua_error(L, "stat index out of range");
return 0;
}
idx--; // actual array is 0 indexed.
WSTAT_L(t);
tus->counters[idx] += change;
WSTAT_UL(t);
return 0;
}
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