/* samp.c -- code for ln_samp objects.
* This code handles rulebase processing. Rulebases have been called
* "sample bases" in the early days of liblognorm, thus the name.
*
* Copyright 2010-2018 by Rainer Gerhards and Adiscon GmbH.
*
* Modified by Pavel Levshin (pavel@levshin.spb.ru) in 2013
*
* This file is part of liblognorm.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*
* A copy of the LGPL v2.1 can be found in the file "COPYING" in this distribution.
*/
#include "config.h"
#include <stdlib.h>
#include <stdio.h>
#include <stdarg.h>
#include <string.h>
#include <assert.h>
#include <ctype.h>
#include <errno.h>
#include "liblognorm.h"
#include "lognorm.h"
#include "samp.h"
#include "internal.h"
#include "parser.h"
#include "pdag.h"
#include "v1_liblognorm.h"
#include "v1_ptree.h"
void
ln_sampFree(ln_ctx __attribute__((unused)) ctx, struct ln_samp *samp)
{
free(samp);
}
static int
ln_parseLegacyFieldDescr(ln_ctx ctx,
const char *const buf,
const size_t lenBuf,
size_t *bufOffs,
es_str_t **str,
json_object **prscnf)
{
int r = 0;
char *cstr; /* for debug mode strings */
char *ftype = NULL;
char name[MAX_FIELDNAME_LEN];
size_t iDst;
struct json_object *json = NULL;
char *ed = NULL;
es_size_t i = *bufOffs;
es_str_t *edata = NULL;
for( iDst = 0
; iDst < (MAX_FIELDNAME_LEN - 1) && i < lenBuf && buf[i] != ':'
; ++iDst) {
name[iDst] = buf[i++];
}
name[iDst] = '\0';
if(iDst == (MAX_FIELDNAME_LEN - 1)) {
ln_errprintf(ctx, 0, "field name too long in: %s", buf+(*bufOffs));
FAIL(LN_INVLDFDESCR);
}
if(i == lenBuf) {
ln_errprintf(ctx, 0, "field definition wrong in: %s", buf+(*bufOffs));
FAIL(LN_INVLDFDESCR);
}
if(iDst == 0) {
FAIL(LN_INVLDFDESCR);
}
if(ctx->debug) {
ln_dbgprintf(ctx, "parsed field: '%s'", name);
}
if(buf[i] != ':') {
ln_errprintf(ctx, 0, "missing colon in: %s", buf+(*bufOffs));
FAIL(LN_INVLDFDESCR);
}
++i; /* skip ':' */
/* parse and process type (trailing whitespace must be trimmed) */
es_emptyStr(*str);
size_t j = i;
/* scan for terminator */
while(j < lenBuf && buf[j] != ':' && buf[j] != '{' && buf[j] != '%')
++j;
/* now trim trailing space backwards */
size_t next = j;
--j;
while(j >= i && isspace(buf[j]))
--j;
/* now copy */
while(i <= j) {
CHKR(es_addChar(str, buf[i++]));
}
/* finally move i to consumed position */
i = next;
if(i == lenBuf) {
ln_errprintf(ctx, 0, "premature end (missing %%?) in: %s", buf+(*bufOffs));
FAIL(LN_INVLDFDESCR);
}
ftype = es_str2cstr(*str, NULL);
ln_dbgprintf(ctx, "field type '%s', i %d", ftype, i);
if(buf[i] == '{') {
struct json_tokener *tokener = json_tokener_new();
json = json_tokener_parse_ex(tokener, buf+i, (int) (lenBuf - i));
if(json == NULL) {
ln_errprintf(ctx, 0, "invalid json in '%s'", buf+i);
}
i += tokener->char_offset;
json_tokener_free(tokener);
}
if(buf[i] == '%') {
i++;
} else {
/* parse extra data */
CHKN(edata = es_newStr(8));
i++;
while(i < lenBuf) {
if(buf[i] == '%') {
++i;
break; /* end of field */
}
CHKR(es_addChar(&edata, buf[i++]));
}
es_unescapeStr(edata);
if(ctx->debug) {
cstr = es_str2cstr(edata, NULL);
ln_dbgprintf(ctx, "parsed extra data: '%s'", cstr);
free(cstr);
}
}
struct json_object *val;
*prscnf = json_object_new_object();
CHKN(val = json_object_new_string(name));
json_object_object_add(*prscnf, "name", val);
CHKN(val = json_object_new_string(ftype));
json_object_object_add(*prscnf, "type", val);
if(edata != NULL) {
ed = es_str2cstr(edata, " ");
CHKN(val = json_object_new_string(ed));
json_object_object_add(*prscnf, "extradata", val);
}
if(json != NULL) {
/* now we need to merge the json params into the main object */
struct json_object_iterator it = json_object_iter_begin(json);
struct json_object_iterator itEnd = json_object_iter_end(json);
while (!json_object_iter_equal(&it, &itEnd)) {
struct json_object *const v = json_object_iter_peek_value(&it);
json_object_get(v);
json_object_object_add(*prscnf, json_object_iter_peek_name(&it), v);
json_object_iter_next(&it);
}
}
*bufOffs = i;
done:
free(ed);
if(edata != NULL)
es_deleteStr(edata);
free(ftype);
if(json != NULL)
json_object_put(json);
return r;
}
/**
* Extract a field description from a sample.
* The field description is added to the tail of the current
* subtree's field list. The parse buffer must be position on the
* leading '%' that starts a field definition. It is a program error
* if this condition is not met.
*
* Note that we break up the object model and access ptree members
* directly. Let's consider us a friend of ptree. This is necessary
* to optimize the structure for a high-speed parsing process.
*
* @param[in] str a temporary work string. This is passed in to save the
* creation overhead
* @returns 0 on success, something else otherwise
*/
static int
addFieldDescr(ln_ctx ctx, struct ln_pdag **pdag, es_str_t *rule,
size_t *bufOffs, es_str_t **str)
{
int r = 0;
es_size_t i = *bufOffs;
char *ftype = NULL;
const char *buf;
es_size_t lenBuf;
struct json_object *prs_config = NULL;
buf = (const char*)es_getBufAddr(rule);
lenBuf = es_strlen(rule);
assert(buf[i] == '%');
++i; /* "eat" ':' */
/* skip leading whitespace in field name */
while(i < lenBuf && isspace(buf[i]))
++i;
/* check if we have new-style json config */
if(buf[i] == '{' || buf[i] == '[') {
struct json_tokener *tokener = json_tokener_new();
prs_config = json_tokener_parse_ex(tokener, buf+i, (int) (lenBuf - i));
i += tokener->char_offset;
json_tokener_free(tokener);
if(prs_config == NULL || i == lenBuf || buf[i] != '%') {
ln_errprintf(ctx, 0, "invalid json in '%s'", buf+i);
r = -1;
goto done;
}
*bufOffs = i+1; /* eat '%' - if above ensures it is present */
} else {
*bufOffs = i;
CHKR(ln_parseLegacyFieldDescr(ctx, buf, lenBuf, bufOffs, str, &prs_config));
}
CHKR(ln_pdagAddParser(ctx, pdag, prs_config));
done:
free(ftype);
return r;
}
/**
* Construct a literal parser json definition.
*/
static json_object *
newLiteralParserJSONConf(char lit)
{
char buf[] = "x";
buf[0] = lit;
struct json_object *val;
struct json_object *prscnf = json_object_new_object();
val = json_object_new_string("literal");
json_object_object_add(prscnf, "type", val);
val = json_object_new_string(buf);
json_object_object_add(prscnf, "text", val);
return prscnf;
}
/**
* Parse a Literal string out of the template and add it to the tree.
* This function is used to create the unoptimized tree. So we do
* one node for each character. These will be compacted by the optimizer
* in a later stage. The advantage is that we do not need to care about
* splitting the tree. As such the processing is fairly simple:
*
* for each character in literal (left-to-right):
* create literal parser object o
* add new DAG node o, advance to it
*
* @param[in] ctx the context
* @param[in/out] subtree on entry, current subtree, on exist newest
* deepest subtree
* @param[in] rule string with current rule
* @param[in/out] bufOffs parse pointer, up to which offset is parsed
* (is updated so that it points to first char after consumed
* string on exit).
* @param str a work buffer, provided to prevent creation of a new object
* @return 0 on success, something else otherwise
*/
static int
parseLiteral(ln_ctx ctx, struct ln_pdag **pdag, es_str_t *rule,
size_t *const __restrict__ bufOffs, es_str_t **str)
{
int r = 0;
size_t i = *bufOffs;
unsigned char *buf = es_getBufAddr(rule);
const size_t lenBuf = es_strlen(rule);
const char *cstr = NULL;
es_emptyStr(*str);
while(i < lenBuf) {
if(buf[i] == '%') {
if(i+1 < lenBuf && buf[i+1] != '%') {
break; /* field start is end of literal */
}
if (++i == lenBuf) break;
}
CHKR(es_addChar(str, buf[i]));
++i;
}
es_unescapeStr(*str);
cstr = es_str2cstr(*str, NULL);
if(ctx->debug) {
ln_dbgprintf(ctx, "parsed literal: '%s'", cstr);
}
*bufOffs = i;
/* we now add the string to the tree */
for(i = 0 ; cstr[i] != '\0' ; ++i) {
struct json_object *const prscnf =
newLiteralParserJSONConf(cstr[i]);
CHKN(prscnf);
CHKR(ln_pdagAddParser(ctx, pdag, prscnf));
}
r = 0;
done:
free((void*)cstr);
return r;
}
/* Implementation note:
* We read in the sample, and split it into chunks of literal text and
* fields. Each literal text is added as whole to the tree, as is each
* field individually. To do so, we keep track of our current subtree
* root, which changes whenever a new part of the tree is build. It is
* set to the then-lowest part of the tree, where the next step sample
* data is to be added.
*
* This function processes the whole string or returns an error.
*
* format: literal1%field:type:extra-data%literal2
*
* @returns the new dag root (or NULL in case of error)
*/
static int
addSampToTree(ln_ctx ctx,
es_str_t *rule,
ln_pdag *dag,
struct json_object *tagBucket)
{
int r = -1;
es_str_t *str = NULL;
size_t i;
CHKN(str = es_newStr(256));
i = 0;
while(i < es_strlen(rule)) {
LN_DBGPRINTF(ctx, "addSampToTree %zu of %d", i, es_strlen(rule));
CHKR(parseLiteral(ctx, &dag, rule, &i, &str));
/* After the literal there can be field only*/
if (i < es_strlen(rule)) {
CHKR(addFieldDescr(ctx, &dag, rule, &i, &str));
if (i == es_strlen(rule)) {
/* finish the tree with empty literal to avoid false merging*/
CHKR(parseLiteral(ctx, &dag, rule, &i, &str));
}
}
}
LN_DBGPRINTF(ctx, "end addSampToTree %zu of %d", i, es_strlen(rule));
/* we are at the end of rule processing, so this node is a terminal */
dag->flags.isTerminal = 1;
dag->tags = tagBucket;
dag->rb_file = strdup(ctx->conf_file);
dag->rb_lineno = ctx->conf_ln_nbr;
done:
if(str != NULL)
es_deleteStr(str);
return r;
}
/**
* get the initial word of a rule line that tells us the type of the
* line.
* @param[in] buf line buffer
* @param[in] len length of buffer
* @param[out] offs offset after "="
* @param[out] str string with "linetype-word" (newly created)
* @returns 0 on success, something else otherwise
*/
static int
getLineType(const char *buf, es_size_t lenBuf, size_t *offs, es_str_t **str)
{
int r = -1;
size_t i;
*str = es_newStr(16);
for(i = 0 ; i < lenBuf && buf[i] != '=' ; ++i) {
CHKR(es_addChar(str, buf[i]));
}
if(i < lenBuf)
++i; /* skip over '=' */
*offs = i;
done: return r;
}
/**
* Get a new common prefix from the config file. That is actually everything from
* the current offset to the end of line.
*
* @param[in] buf line buffer
* @param[in] len length of buffer
* @param[in] offs offset after "="
* @param[in/out] str string to store common offset. If NULL, it is created,
* otherwise it is emptied.
* @returns 0 on success, something else otherwise
*/
static int
getPrefix(const char *buf, es_size_t lenBuf, es_size_t offs, es_str_t **str)
{
int r;
if(*str == NULL) {
CHKN(*str = es_newStr(lenBuf - offs));
} else {
es_emptyStr(*str);
}
r = es_addBuf(str, (char*)buf + offs, lenBuf - offs);
done: return r;
}
/**
* Extend the common prefix. This means that the line is concatenated
* to the prefix. This is useful if the same rulebase is to be used with
* different prefixes (well, not strictly necessary, but probably useful).
*
* @param[in] ctx current context
* @param[in] buf line buffer
* @param[in] len length of buffer
* @param[in] offs offset to-be-added text starts
* @returns 0 on success, something else otherwise
*/
static int
extendPrefix(ln_ctx ctx, const char *buf, es_size_t lenBuf, es_size_t offs)
{
return es_addBuf(&ctx->rulePrefix, (char*)buf+offs, lenBuf - offs);
}
/**
* Add a tag to the tag bucket. Helper to processTags.
* @param[in] ctx current context
* @param[in] tagname string with tag name
* @param[out] tagBucket tagbucket to which new tags shall be added
* the tagbucket is created if it is NULL
* @returns 0 on success, something else otherwise
*/
static int
addTagStrToBucket(ln_ctx ctx, es_str_t *tagname, struct json_object **tagBucket)
{
int r = -1;
char *cstr;
struct json_object *tag;
if(*tagBucket == NULL) {
CHKN(*tagBucket = json_object_new_array());
}
cstr = es_str2cstr(tagname, NULL);
ln_dbgprintf(ctx, "tag found: '%s'", cstr);
CHKN(tag = json_object_new_string(cstr));
json_object_array_add(*tagBucket, tag);
free(cstr);
r = 0;
done: return r;
}
/**
* Extract the tags and create a tag bucket out of them
*
* @param[in] ctx current context
* @param[in] buf line buffer
* @param[in] len length of buffer
* @param[in,out] poffs offset where tags start, on exit and success
* offset after tag part (excluding ':')
* @param[out] tagBucket tagbucket to which new tags shall be added
* the tagbucket is created if it is NULL
* @returns 0 on success, something else otherwise
*/
static int
processTags(ln_ctx ctx, const char *buf, es_size_t lenBuf, es_size_t *poffs, struct json_object **tagBucket)
{
int r = -1;
es_str_t *str = NULL;
es_size_t i;
assert(poffs != NULL);
i = *poffs;
while(i < lenBuf && buf[i] != ':') {
if(buf[i] == ',') {
/* end of this tag */
CHKR(addTagStrToBucket(ctx, str, tagBucket));
es_deleteStr(str);
str = NULL;
} else {
if(str == NULL) {
CHKN(str = es_newStr(32));
}
CHKR(es_addChar(&str, buf[i]));
}
++i;
}
if(buf[i] != ':')
goto done;
++i; /* skip ':' */
if(str != NULL) {
CHKR(addTagStrToBucket(ctx, str, tagBucket));
es_deleteStr(str);
}
*poffs = i;
r = 0;
done: return r;
}
/**
* Process a new rule and add it to pdag.
*
* @param[in] ctx current context
* @param[in] buf line buffer
* @param[in] len length of buffer
* @param[in] offs offset where rule starts
* @returns 0 on success, something else otherwise
*/
static int
processRule(ln_ctx ctx, const char *buf, es_size_t lenBuf, es_size_t offs)
{
int r = -1;
es_str_t *str;
struct json_object *tagBucket = NULL;
ln_dbgprintf(ctx, "rule line to add: '%s'", buf+offs);
CHKR(processTags(ctx, buf, lenBuf, &offs, &tagBucket));
if(offs == lenBuf) {
ln_errprintf(ctx, 0, "error: actual message sample part is missing");
goto done;
}
if(ctx->rulePrefix == NULL) {
CHKN(str = es_newStr(lenBuf));
} else {
CHKN(str = es_strdup(ctx->rulePrefix));
}
CHKR(es_addBuf(&str, (char*)buf + offs, lenBuf - offs));
addSampToTree(ctx, str, ctx->pdag, tagBucket);
es_deleteStr(str);
r = 0;
done: return r;
}
static int
getTypeName(ln_ctx ctx,
const char *const __restrict__ buf,
const size_t lenBuf,
size_t *const __restrict__ offs,
char *const __restrict__ dstbuf)
{
int r = -1;
size_t iDst;
size_t i = *offs;
if(buf[i] != '@') {
ln_errprintf(ctx, 0, "user-defined type name must "
"start with '@'");
goto done;
}
for( iDst = 0
; i < lenBuf && buf[i] != ':' && iDst < MAX_TYPENAME_LEN - 1
; ++i, ++iDst) {
if(isspace(buf[i])) {
ln_errprintf(ctx, 0, "user-defined type name must "
"not contain whitespace");
goto done;
}
dstbuf[iDst] = buf[i];
}
dstbuf[iDst] = '\0';
if(i < lenBuf && buf[i] == ':') {
r = 0,
*offs = i+1; /* skip ":" */
}
done:
return r;
}
/**
* Process a type definition and add it to the PDAG
* disconnected components.
*
* @param[in] ctx current context
* @param[in] buf line buffer
* @param[in] len length of buffer
* @param[in] offs offset where rule starts
* @returns 0 on success, something else otherwise
*/
static int
processType(ln_ctx ctx,
const char *const __restrict__ buf,
const size_t lenBuf,
size_t offs)
{
int r = -1;
es_str_t *str;
char typename[MAX_TYPENAME_LEN];
ln_dbgprintf(ctx, "type line to add: '%s'", buf+offs);
CHKR(getTypeName(ctx, buf, lenBuf, &offs, typename));
ln_dbgprintf(ctx, "type name is '%s'", typename);
ln_dbgprintf(ctx, "type line to add: '%s'", buf+offs);
if(offs == lenBuf) {
ln_errprintf(ctx, 0, "error: actual message sample part is missing in type def");
goto done;
}
// TODO: optimize
CHKN(str = es_newStr(lenBuf));
CHKR(es_addBuf(&str, (char*)buf + offs, lenBuf - offs));
struct ln_type_pdag *const td = ln_pdagFindType(ctx, typename, 1);
CHKN(td);
addSampToTree(ctx, str, td->pdag, NULL);
es_deleteStr(str);
r = 0;
done: return r;
}
/**
* Obtain a field name from a rule base line.
*
* @param[in] ctx current context
* @param[in] buf line buffer
* @param[in] len length of buffer
* @param[in/out] offs on entry: offset where tag starts,
* on exit: updated offset AFTER TAG and (':')
* @param [out] strTag obtained tag, if successful
* @returns 0 on success, something else otherwise
*/
static int
getFieldName(ln_ctx __attribute__((unused)) ctx, const char *buf, es_size_t lenBuf, es_size_t *offs,
es_str_t **strTag)
{
int r = -1;
es_size_t i;
i = *offs;
while(i < lenBuf &&
(isalnum(buf[i]) || buf[i] == '_' || buf[i] == '.')) {
if(*strTag == NULL) {
CHKN(*strTag = es_newStr(32));
}
CHKR(es_addChar(strTag, buf[i]));
++i;
}
*offs = i;
r = 0;
done: return r;
}
/**
* Skip over whitespace.
* Skips any whitespace present at the offset.
*
* @param[in] ctx current context
* @param[in] buf line buffer
* @param[in] len length of buffer
* @param[in/out] offs on entry: offset first unprocessed position
*/
static void
skipWhitespace(ln_ctx __attribute__((unused)) ctx, const char *buf, es_size_t lenBuf, es_size_t *offs)
{
while(*offs < lenBuf && isspace(buf[*offs])) {
(*offs)++;
}
}
/**
* Obtain an annotation (field) operation.
* This usually is a plus or minus sign followed by a field name
* followed (if plus) by an equal sign and the field value. On entry,
* offs must be positioned on the first unprocessed field (after ':' for
* the initial field!). Extra whitespace is detected and, if present,
* skipped. The obtained operation is added to the annotation set provided.
* Note that extracted string objects are passed to the annotation; thus it
* is vital NOT to free them (most importantly, this is *not* a memory leak).
*
* @param[in] ctx current context
* @param[in] annot active annotation set to which the operation is to be added
* @param[in] buf line buffer
* @param[in] len length of buffer
* @param[in/out] offs on entry: offset where tag starts,
* on exit: updated offset AFTER TAG and (':')
* @param [out] strTag obtained tag, if successful
* @returns 0 on success, something else otherwise
*/
static int
getAnnotationOp(ln_ctx ctx, ln_annot *annot, const char *buf, es_size_t lenBuf, es_size_t *offs)
{
int r = -1;
es_size_t i;
es_str_t *fieldName = NULL;
es_str_t *fieldVal = NULL;
ln_annot_opcode opc;
i = *offs;
skipWhitespace(ctx, buf, lenBuf, &i);
if(i == lenBuf) {
r = 0;
goto done; /* nothing left to process (no error!) */
}
switch(buf[i]) {
case '+':
opc = ln_annot_ADD;
break;
case '#':
ln_dbgprintf(ctx, "inline comment in 'annotate' line: %s", buf);
*offs = lenBuf;
r = 0;
goto done;
case '-':
ln_dbgprintf(ctx, "annotate op '-' not yet implemented - failing");
/*FALLTHROUGH*/
default:ln_errprintf(ctx, 0, "invalid annotate operation '%c': %s", buf[i], buf+i);
goto fail;
}
i++;
if(i == lenBuf) goto fail; /* nothing left to process */
CHKR(getFieldName(ctx, buf, lenBuf, &i, &fieldName));
if(i == lenBuf) goto fail; /* nothing left to process */
if(buf[i] != '=') goto fail; /* format error */
i++;
skipWhitespace(ctx, buf, lenBuf, &i);
if(buf[i] != '"') goto fail; /* format error */
++i;
while(i < lenBuf && buf[i] != '"') {
if(fieldVal == NULL) {
CHKN(fieldVal = es_newStr(32));
}
CHKR(es_addChar(&fieldVal, buf[i]));
++i;
}
*offs = (i == lenBuf) ? i : i+1;
CHKR(ln_addAnnotOp(annot, opc, fieldName, fieldVal));
r = 0;
done: return r;
fail: return -1;
}
/**
* Process a new annotation and add it to the annotation set.
*
* @param[in] ctx current context
* @param[in] buf line buffer
* @param[in] len length of buffer
* @param[in] offs offset where annotation starts
* @returns 0 on success, something else otherwise
*/
static int
processAnnotate(ln_ctx ctx, const char *buf, es_size_t lenBuf, es_size_t offs)
{
int r;
es_str_t *tag = NULL;
ln_annot *annot;
ln_dbgprintf(ctx, "sample annotation to add: '%s'", buf+offs);
CHKR(getFieldName(ctx, buf, lenBuf, &offs, &tag));
skipWhitespace(ctx, buf, lenBuf, &offs);
if(buf[offs] != ':' || tag == NULL) {
ln_dbgprintf(ctx, "invalid tag field in annotation, line is '%s'", buf);
r=-1;
goto done;
}
++offs;
/* we got an annotation! */
CHKN(annot = ln_newAnnot(tag));
while(offs < lenBuf) {
CHKR(getAnnotationOp(ctx, annot, buf, lenBuf, &offs));
}
r = ln_addAnnotToSet(ctx->pas, annot);
done: return r;
}
/**
* Process include directive. This permits to add unlimited layers
* of include files.
*
* @param[in] ctx current context
* @param[in] buf line buffer, a C-string
* @param[in] offs offset where annotation starts
* @returns 0 on success, something else otherwise
*/
static int
processInclude(ln_ctx ctx, const char *buf, const size_t offs)
{
int r;
const char *const conf_file_save = ctx->conf_file;
char *const fname = strdup(buf+offs);
size_t lenfname = strlen(fname);
const unsigned conf_ln_nbr_save = ctx->conf_ln_nbr;
/* trim string - not optimized but also no need to */
for(size_t i = lenfname - 1 ; i > 0 ; --i) {
if(isspace(fname[i])) {
fname[i] = '\0';
--lenfname;
}
}
CHKR(ln_loadSamples(ctx, fname));
done:
free(fname);
ctx->conf_file = conf_file_save;
ctx->conf_ln_nbr = conf_ln_nbr_save;
return r;
}
/**
* Reads a rule (sample) stored in buffer buf and creates a new ln_samp object
* out of it, which it adds to the pdag (if required).
*
* @param[ctx] ctx current library context
* @param[buf] cstr buffer containing the string contents of the sample
* @param[lenBuf] length of the sample contained within buf
* @return standard error code
*/
static int
ln_processSamp(ln_ctx ctx, const char *buf, const size_t lenBuf)
{
int r = 0;
es_str_t *typeStr = NULL;
size_t offs;
if(getLineType(buf, lenBuf, &offs, &typeStr) != 0)
goto done;
if(!es_strconstcmp(typeStr, "prefix")) {
if(getPrefix(buf, lenBuf, offs, &ctx->rulePrefix) != 0) goto done;
} else if(!es_strconstcmp(typeStr, "extendprefix")) {
if(extendPrefix(ctx, buf, lenBuf, offs) != 0) goto done;
} else if(!es_strconstcmp(typeStr, "rule")) {
if(processRule(ctx, buf, lenBuf, offs) != 0) goto done;
} else if(!es_strconstcmp(typeStr, "type")) {
if(processType(ctx, buf, lenBuf, offs) != 0) goto done;
} else if(!es_strconstcmp(typeStr, "annotate")) {
if(processAnnotate(ctx, buf, lenBuf, offs) != 0) goto done;
} else if(!es_strconstcmp(typeStr, "include")) {
CHKR(processInclude(ctx, buf, offs));
} else {
char *str;
str = es_str2cstr(typeStr, NULL);
ln_errprintf(ctx, 0, "invalid record type detected: '%s'", str);
free(str);
goto done;
}
done:
if(typeStr != NULL)
es_deleteStr(typeStr);
return r;
}
/**
* Read a character from our sample source.
*/
static int
ln_sampReadChar(const ln_ctx ctx, FILE *const __restrict__ repo, const char **inpbuf)
{
int c;
assert((repo != NULL && inpbuf == NULL) || (repo == NULL && inpbuf != NULL));
if(repo == NULL) {
c = (**inpbuf == '\0') ? EOF : *(*inpbuf)++;
} else {
c = fgetc(repo);
}
return c;
}
/* note: comments are only supported at beginning of line! */
/* skip to end of line */
void
ln_sampSkipCommentLine(ln_ctx ctx, FILE * const __restrict__ repo, const char **inpbuf)
{
int c;
do {
c = ln_sampReadChar(ctx, repo, inpbuf);
} while(c != EOF && c != '\n');
++ctx->conf_ln_nbr;
}
/* this checks if in a multi-line rule, the next line seems to be a new
* rule, which would meand we have some unmatched percent signs inside
* our rule (what we call a "runaway rule"). This can easily happen and
* is otherwise hard to debug, so let's see if it is the case...
* @return 1 if this is a runaway rule, 0 if not
*/
int
ln_sampChkRunawayRule(ln_ctx ctx, FILE *const __restrict__ repo, const char **inpbuf)
{
int r = 1;
fpos_t fpos;
char buf[6];
int cont = 1;
int read;
fgetpos(repo, &fpos);
while(cont) {
fpos_t inner_fpos;
fgetpos(repo, &inner_fpos);
if((read = fread(buf, sizeof(char), sizeof(buf)-1, repo)) == 0) {
r = 0;
goto done;
}
if(buf[0] == '\n') {
fsetpos(repo, &inner_fpos);
if(fread(buf, sizeof(char), 1, repo)) {}; /* skip '\n' */
continue;
} else if(buf[0] == '#') {
fsetpos(repo, &inner_fpos);
const unsigned conf_ln_nbr_save = ctx->conf_ln_nbr;
ln_sampSkipCommentLine(ctx, repo, inpbuf);
ctx->conf_ln_nbr = conf_ln_nbr_save;
continue;
}
if(read != 5)
goto done; /* cannot be a rule= line! */
cont = 0; /* no comment, so we can decide */
buf[5] = '\0';
if(!strncmp(buf, "rule=", 5)) {
ln_errprintf(ctx, 0, "line has 'rule=' at begin of line, which "
"does look like a typo in the previous lines (unmatched "
"%% character) and is forbidden. If valid, please re-format "
"the rule to start with other characters. Rule ignored.");
goto done;
}
}
r = 0;
done:
fsetpos(repo, &fpos);
return r;
}
/**
* Read a rule (sample) from repository (sequentially).
*
* Reads a sample starting with the current file position and
* creates a new ln_samp object out of it, which it adds to the
* pdag.
*
* @param[in] ctx current library context
* @param[in] repo repository descriptor if file input is desired
* @param[in/out] ptr to ptr of input buffer; this is used if a string is
* provided instead of a file. If so, this pointer is advanced
* as data is consumed.
* @param[out] isEof must be set to 0 on entry and is switched to 1 if EOF occured.
* @return standard error code
*/
static int
ln_sampRead(ln_ctx ctx, FILE *const __restrict__ repo, const char **inpbuf,
int *const __restrict__ isEof)
{
int r = 0;
char buf[64*1024]; /**< max size of rule - TODO: make configurable */
size_t i = 0;
int inParser = 0;
int done = 0;
while(!done) {
const int c = ln_sampReadChar(ctx, repo, inpbuf);
if(c == EOF) {
*isEof = 1;
if(i == 0)
goto done;
else
done = 1; /* last line missing LF, still process it! */
} else if(c == '\n') {
++ctx->conf_ln_nbr;
if(inParser) {
if(ln_sampChkRunawayRule(ctx, repo, inpbuf)) {
/* ignore previous rule */
inParser = 0;
i = 0;
}
}
if(!inParser && i != 0)
done = 1;
} else if(c == '#' && i == 0) {
ln_sampSkipCommentLine(ctx, repo, inpbuf);
i = 0; /* back to beginning */
} else {
if(c == '%')
inParser = (inParser) ? 0 : 1;
buf[i++] = c;
if(i >= sizeof(buf)) {
ln_errprintf(ctx, 0, "line is too long");
goto done;
}
}
}
buf[i] = '\0';
ln_dbgprintf(ctx, "read rulebase line[~%d]: '%s'", ctx->conf_ln_nbr, buf);
CHKR(ln_processSamp(ctx, buf, i));
done:
return r;
}
/* check rulebase format version. Returns 2 if this is v2 rulebase,
* 1 for any pre-v2 and -1 if there was a problem reading the file.
*/
static int
checkVersion(FILE *const fp)
{
char buf[64];
if(fgets(buf, sizeof(buf), fp) == NULL)
return -1;
if(!strcmp(buf, "version=2\n")) {
return 2;
} else {
return 1;
}
}
/* we have a v1 rulebase, so let's do all stuff that we need
* to make that ole piece of ... work.
*/
static int
doOldCruft(ln_ctx ctx, const char *file)
{
int r = -1;
if((ctx->ptree = ln_newPTree(ctx, NULL)) == NULL) {
free(ctx);
r = -1;
goto done;
}
r = ln_v1_loadSamples(ctx, file);
done:
return r;
}
/* try to open a rulebase file. This also tries to see if we need to
* load it from some pre-configured alternative location.
* @returns open file pointer or NULL in case of error
*/
static FILE *
tryOpenRBFile(ln_ctx ctx, const char *const file)
{
FILE *repo = NULL;
if((repo = fopen(file, "r")) != NULL)
goto done;
const int eno1 = errno;
const char *const rb_lib = getenv("LIBLOGNORM_RULEBASES");
if(rb_lib == NULL || *file == '/') {
ln_errprintf(ctx, eno1, "cannot open rulebase '%s'", file);
goto done;
}
char *fname = NULL;
int len;
len = asprintf(&fname, (rb_lib[strlen(rb_lib)-1] == '/') ? "%s%s" : "%s/%s", rb_lib, file);
if(len == -1) {
ln_errprintf(ctx, errno, "alloc error: cannot open rulebase '%s'", file);
goto done;
}
if((repo = fopen(fname, "r")) == NULL) {
const int eno2 = errno;
ln_errprintf(ctx, eno1, "cannot open rulebase '%s'", file);
ln_errprintf(ctx, eno2, "also tried to locate %s via "
"rulebase directory without success. Expanded "
"name was '%s'", file, fname);
}
free(fname);
done:
return repo;
}
/* @return 0 if all is ok, 1 if an error occured */
int
ln_sampLoad(ln_ctx ctx, const char *file)
{
int r = 1;
FILE *repo;
int isEof = 0;
ln_dbgprintf(ctx, "loading rulebase file '%s'", file);
if(file == NULL) goto done;
if((repo = tryOpenRBFile(ctx, file)) == NULL)
goto done;
const int version = checkVersion(repo);
ln_dbgprintf(ctx, "rulebase version is %d\n", version);
if(version == -1) {
ln_errprintf(ctx, errno, "error determing version of %s", file);
goto done;
}
if(ctx->version != 0 && version != ctx->version) {
ln_errprintf(ctx, errno, "rulebase '%s' must be version %d, but is version %d "
" - can not be processed", file, ctx->version, version);
goto done;
}
ctx->version = version;
if(ctx->version == 1) {
fclose(repo);
r = doOldCruft(ctx, file);
goto done;
}
/* now we are in our native code */
++ctx->conf_ln_nbr; /* "version=2" is line 1! */
while(!isEof) {
CHKR(ln_sampRead(ctx, repo, NULL, &isEof));
}
fclose(repo);
r = 0;
if(ctx->include_level == 1)
ln_pdagOptimize(ctx);
done:
return r;
}
/* @return 0 if all is ok, 1 if an error occured */
int
ln_sampLoadFromString(ln_ctx ctx, const char *string)
{
int r = 1;
int isEof = 0;
if(string == NULL)
goto done;
ln_dbgprintf(ctx, "loading v2 rulebase from string '%s'", string);
ctx->version = 2;
while(!isEof) {
CHKR(ln_sampRead(ctx, NULL, &string, &isEof));
}
r = 0;
if(ctx->include_level == 1)
ln_pdagOptimize(ctx);
done:
return r;
}