ossp-pkg/cfg/cfg_syn.c
1.26
/*
** OSSP cfg - Configuration Parsing
** Copyright (c) 2002-2006 Ralf S. Engelschall <rse@engelschall.com>
** Copyright (c) 2002-2006 The OSSP Project (http://www.ossp.org/)
**
** This file is part of OSSP cfg, a configuration parsing
** library which can be found at http://www.ossp.org/pkg/lib/cfg/.
**
** Permission to use, copy, modify, and distribute this software for
** any purpose with or without fee is hereby granted, provided that
** the above copyright notice and this permission notice appear in all
** copies.
**
** THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
** WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
** MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
** IN NO EVENT SHALL THE AUTHORS AND COPYRIGHT HOLDERS AND THEIR
** CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
** USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
** ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
** OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
** OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
** SUCH DAMAGE.
**
** cfg_syn.c: syntax parsing and formatting
*/
#include <stdio.h>
#include <ctype.h>
#include "cfg.h"
#include "cfg_grid.h"
#include "cfg_node.h"
#include "cfg_fmt.h"
#include "cfg_syn.h"
#include "cfg_buf.h"
#include "cfg_global.h"
/* prototypes for Flex-generated scanner */
extern int cfg_syn_lex_init(void *);
extern int cfg_syn_lex_destroy(void *);
extern void cfg_syn_set_extra(void *, void *);
/* prototypes for Bison-generated parser */
extern int cfg_syn_parse(void *);
/* build a node tree according to a textual specification */
cfg_rc_t cfg_syn_import(
cfg_t *cfg,
cfg_node_t **node,
const char *in_ptr,
size_t in_len,
char *err_buf,
size_t err_len)
{
cfg_syn_ctx_t ctx;
cfg_buf_t *buf;
cfg_rc_t rc;
void *yyscan;
/* argument sanity checking */
if (node == NULL || in_ptr == NULL)
return CFG_ERR_ARG;
/* initialize scanner */
cfg_syn_lex_init(&yyscan);
cfg_syn_set_extra(&ctx, yyscan);
/* initialize temporary buffer context */
if ((rc = cfg_buf_create(&buf)) != CFG_OK)
return rc;
/* establish our own context which is passed
through the parser and scanner */
ctx.inputptr = in_ptr;
ctx.inputbuf = in_ptr;
ctx.inputlen = in_len;
ctx.cfg = cfg;
ctx.node = NULL;
ctx.rv = CFG_OK;
ctx.buf = buf;
ctx.err_buf = err_buf;
ctx.err_len = err_len;
ctx.yyscan = yyscan;
/* start the parser loop */
if (cfg_syn_parse(&ctx))
ctx.rv = (ctx.rv == CFG_OK ? CFG_ERR_INT : ctx.rv);
/* destroy temporary buffer */
cfg_buf_destroy(buf);
/* destroy scanner */
cfg_syn_lex_destroy(yyscan);
/* provide root/top-level node as result */
*node = ctx.node;
return ctx.rv;
}
/* helper function for copying out input with escaping of characters */
static size_t cfg_syn_error_cpyout(char *out_ptr, const char *in_ptr, size_t in_len)
{
size_t out_len;
char c;
out_len = 0;
while (in_len-- > 0) {
c = *in_ptr++;
switch (c) {
case '\n': *out_ptr++ = '\\'; *out_ptr++ = 'n'; out_len += 2; break;
case '\r': *out_ptr++ = '\\'; *out_ptr++ = 'r'; out_len += 2; break;
case '\t': *out_ptr++ = '\\'; *out_ptr++ = 't'; out_len += 2; break;
case '\b': *out_ptr++ = '\\'; *out_ptr++ = 'b'; out_len += 2; break;
case '\f': *out_ptr++ = '\\'; *out_ptr++ = 'f'; out_len += 2; break;
default: {
if (!isprint((int)c)) {
*out_ptr++ = '\\';
*out_ptr++ = '?';
out_len += 2;
}
else {
*out_ptr++ = c;
out_len++;
}
}
}
}
return out_len;
}
/* remember a parsing error (used internally) */
void cfg_syn_error(cfg_syn_ctx_t *ctx, cfg_rc_t rv, YYLTYPE *loc, const char *fmt, ...)
{
va_list ap;
const char *cpF, *cpL;
const char *cpP, *cpE;
int line, column;
char *cpBuf;
char *cp;
size_t n;
/* remember error code */
ctx->rv = rv;
/* short circuit processing if no error buffer exists */
if (ctx->err_buf == NULL || ctx->err_len <= 0)
return;
/* determine first and last positions of token */
cpF = ctx->inputbuf+loc->first;
if (cpF < ctx->inputbuf)
cpF = ctx->inputbuf;
if (cpF > ctx->inputbuf+ctx->inputlen)
cpF = ctx->inputbuf+ctx->inputlen;
cpL = ctx->inputbuf+loc->last;
if (cpL < ctx->inputbuf)
cpL = ctx->inputbuf;
if (cpL > ctx->inputbuf+ctx->inputlen)
cpL = ctx->inputbuf+ctx->inputlen;
/* determine epilog and prolog of token */
cpP = cpF-4;
if (cpP < ctx->inputbuf)
cpP = ctx->inputbuf;
cpE = cpL+4;
if (cpE > ctx->inputbuf+ctx->inputlen)
cpE = ctx->inputbuf+ctx->inputlen;
/* calculate line and column of token */
line = 1;
column = 1;
for (cp = (char *)ctx->inputbuf; cp < (ctx->inputbuf+ctx->inputlen) && cp != cpF; cp++) {
column++;
if (*cp == '\n') {
column = 1;
line++;
}
}
/* extract token context with mark token borders */
if ((cpBuf = malloc((size_t)(((cpE-cpP)*2)+2+1))) == NULL)
return;
cp = cpBuf;
cp += cfg_syn_error_cpyout(cp, cpP, cpF-cpP);
*cp++ = '<';
cp += cfg_syn_error_cpyout(cp, cpF, cpL-cpF);
*cp++ = '>';
cp += cfg_syn_error_cpyout(cp, cpL, cpE-cpL);
*cp++ = '\0';
/* remember parsing error: part I (context part) */
cfg_fmt_sprintf(ctx->err_buf, ctx->err_len,
"line %d, column %d: `%s': ",
line, column, cpBuf);
free(cpBuf);
/* remember parsing error: part II (parsing part) */
n = strlen(ctx->err_buf);
va_start(ap, fmt);
cfg_fmt_vsprintf(ctx->err_buf+n, ctx->err_len-n, fmt, ap);
va_end(ap);
return;
}
/* internal cfg_syn_export structure */
typedef struct {
cfg_t *cfg;
cfg_buf_t *buf;
int indent;
} export_t;
/* internal cfg_syn_export helper function: sprintf(3) style output formatting */
static void export_format(export_t *ctx, char *fmt, ...)
{
int i;
char *cp;
char *cp2;
va_list ap;
char *str;
va_start(ap, fmt);
if ((str = cfg_fmt_vasprintf(fmt, ap)) == NULL)
return;
cp = str;
while ((cp2 = strchr(cp, '\n')) != NULL) {
cfg_buf_format(ctx->buf, "%.*s", cp2-cp+1, cp);
for (i = 0; i < ctx->indent; i++)
cfg_buf_format(ctx->buf, " ");
cp = cp2+1;
}
if (cp[0] != '\0')
cfg_buf_format(ctx->buf, "%s", cp);
free(str);
va_end(ap);
return;
}
/* internal cfg_syn_export helper function: indentation handling */
static void export_indent(export_t *ctx, signed int n)
{
if (n > 0) {
while (n > 0) {
n--;
ctx->indent++;
cfg_buf_format(ctx->buf, " ");
}
}
else {
while (n < 0 && ctx->indent > 0) {
n++;
ctx->indent--;
cfg_buf_resize(ctx->buf, -4);
}
}
}
/* internal cfg_syn_export helper function: token output formatting */
static void export_token(export_t *ctx, const char *token)
{
const char *cp;
char *out;
int plain;
char c;
plain = 1;
for (cp = token; *cp != '\0'; cp++) {
if ( !isprint((int)(*cp))
|| strchr(" \n\r\t\b\f;{}\\\"'", (int)(*cp)) != NULL) {
plain = 0;
break;
}
}
if (plain)
export_format(ctx, "%s", token);
else {
export_format(ctx, "\"");
cp = token;
while ((c = *cp++) != '\0') {
out = NULL;
switch (c) {
case '\n': out = "\\n"; break;
case '\r': out = "\\r"; break;
case '\t': out = "\\t"; break;
case '\b': out = "\\b"; break;
case '\f': out = "\\f"; break;
case '\\': out = "\\\\"; break;
case '"' : out = "\\\""; break;
}
if (out != NULL)
export_format(ctx, "%s", out);
else {
if (isprint((int)c))
export_format(ctx, "%c", c);
else
export_format(ctx, "\\x%02x", c);
}
}
export_format(ctx, "\"");
}
return;
}
/* internal cfg_syn_export helper function: recursive node processing */
static void export_node(export_t *ctx, cfg_node_t *node)
{
cfg_node_type_t type;
cfg_node_t *node2;
cfg_rc_t rc;
char *token;
if ((rc = cfg_node_get(ctx->cfg, node, CFG_NODE_ATTR_TYPE, &type)) != CFG_OK)
return;
if (type == CFG_NODE_TYPE_SEQ) {
/* node is a sequence */
export_format(ctx, "{\n");
export_indent(ctx, 1);
cfg_node_get(ctx->cfg, node, CFG_NODE_ATTR_CHILD1, &node2);
while (node2 != NULL) {
export_node(ctx, node2); /* recursion */
cfg_node_get(ctx->cfg, node2, CFG_NODE_ATTR_RBROTH, &node2);
}
export_indent(ctx, -1);
export_format(ctx, "}");
}
else if (type == CFG_NODE_TYPE_DIR) {
/* node is a directive */
cfg_node_get(ctx->cfg, node, CFG_NODE_ATTR_CHILD1, &node2);
while (node2 != NULL) {
export_node(ctx, node2); /* recursion */
cfg_node_get(ctx->cfg, node2, CFG_NODE_ATTR_RBROTH, &node2);
if (node2 != NULL)
export_format(ctx, " ");
}
cfg_node_get(ctx->cfg, node, CFG_NODE_ATTR_RBROTH, &node2);
if (node2 != NULL)
export_format(ctx, ";");
export_format(ctx, "\n");
}
else if (type == CFG_NODE_TYPE_ARG) {
/* node is a token */
cfg_node_get(ctx->cfg, node, CFG_NODE_ATTR_TOKEN, &token);
if (token != NULL)
export_token(ctx, token);
else
export_format(ctx, "<?>");
}
return;
}
/* export configuration node tree into textual OSSP cfg syntax */
cfg_rc_t cfg_syn_export(
cfg_t *cfg,
cfg_node_t *node,
char **output)
{
cfg_buf_t *buf;
cfg_rc_t rc;
export_t ctx;
cfg_node_t *root;
if (node == NULL || output == NULL)
return CFG_ERR_ARG;
if ((rc = cfg_buf_create(&buf)) != CFG_OK)
return rc;
ctx.cfg = cfg;
ctx.buf = buf;
ctx.indent = 0;
if ((rc = cfg_node_root(cfg, NULL, &root)) != CFG_OK)
return rc;
if (node == root) {
/* if we dump the whole configuration, treat the first SEQ node special
because of the implicit braces around it. So expand it manually instead
of just calling once export_node(&ctx, node); */
cfg_node_get(cfg, node, CFG_NODE_ATTR_CHILD1, &node);
while (node != NULL) {
export_node(&ctx, node);
cfg_node_get(cfg, node, CFG_NODE_ATTR_RBROTH, &node);
}
}
else {
export_node(&ctx, node);
}
cfg_buf_content(buf, output, NULL, NULL);
cfg_buf_destroy(buf);
return CFG_OK;
}
/* internal cfg_syn_destroy helper function: recursive node destruction */
static cfg_rc_t cfg_syn_destroy_node(cfg_t *cfg, cfg_node_t *node)
{
if (node == NULL)
return CFG_ERR_ARG;
if (node->child1 != NULL)
cfg_syn_destroy_node(cfg, node->child1); /* recursion */
if (node->rbroth != NULL)
cfg_syn_destroy_node(cfg, node->rbroth); /* recursion */
cfg_node_destroy(cfg, node);
return CFG_OK;
}
/* destroy syntax node tree */
cfg_rc_t cfg_syn_destroy(cfg_t *cfg, cfg_node_t *node)
{
if (node == NULL)
return CFG_ERR_ARG;
cfg_syn_destroy_node(cfg, node);
return CFG_OK;
}
