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implement small optimization on arg parse

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zawz 2021-08-14 13:09:45 +02:00
parent 536168eee4
commit 4ff253a364
2 changed files with 52 additions and 30 deletions
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12
include/parse.hpp
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@ -26,7 +26,15 @@
#define SPECIAL_VARS "!#*@$?"
// bash specific
#define ARRAY_ARG_END " \t\n;#()&|<>]"
#define ARRAY_ARG_END " \t\n;#()&|<>]"
// optimizations
#define ARG_OPTIMIZE_NULL "$\\`"
#define ARG_OPTIMIZE_MANIP "$\\`}"
#define ARG_OPTIMIZE_DEFARR "$\\`)"
#define ARG_OPTIMIZE_BASHTEST "$\\`] \t\n"
#define ARG_OPTIMIZE_ARG "$\\` \t\n;#()&|<>\"'"
#define ARG_OPTIMIZE_ARRAY "$\\`\t\n&|}[]\"'"
#define ARG_OPTIMIZE_ALL "$\\` \t\n;#()&|<>}]\"'"
// structs
@ -100,7 +108,7 @@ std::pair<variable*, parse_context> parse_var(parse_context ct, bool specialvars
std::pair<arithmetic*, parse_context> parse_arithmetic(parse_context ct);
std::pair<variable*, parse_context> parse_manipulation(parse_context ct);
// arg parser
std::pair<arg*, parse_context> parse_arg(parse_context ct, const char* end=ARG_END, const char* unexpected=ARGLIST_END, bool doquote=true);
std::pair<arg*, parse_context> parse_arg(parse_context ct, const char* end=ARG_END, const char* unexpected=ARGLIST_END, bool doquote=true, const char* optimize=ARG_OPTIMIZE_ARG);
// redirect parser
std::pair<redirect*, parse_context> parse_redirect(parse_context ct);
// arglist parser

70
src/parse.cpp
View file

@ -231,7 +231,7 @@ std::pair<variable*, parse_context> parse_var(parse_context ctx, bool specialvar
if(ctx.bash && array && ctx[ctx.i]=='[')
{
ctx.i++;
auto pp=parse_arg(ctx, ARRAY_ARG_END);
auto pp=parse_arg(ctx, ARRAY_ARG_END, ARGLIST_END, true, ARG_OPTIMIZE_ARRAY);
ret->index=pp.first;
ctx = pp.second;
if(ctx[ctx.i] != ']')
@ -409,7 +409,7 @@ std::pair<variable*, parse_context> parse_manipulation(parse_context ctx)
}
else if(ctx[ctx.i] != '}')
{
auto pa = parse_arg(ctx, "}", NULL, false);
auto pa = parse_arg(ctx, "}", NULL, false, ARG_OPTIMIZE_MANIP);
ret->manip=pa.first;
ctx = pa.second;
}
@ -418,14 +418,13 @@ std::pair<variable*, parse_context> parse_manipulation(parse_context ctx)
return std::make_pair(ret, ctx);
}
parse_context do_one_subarg_step(arg* ret, parse_context ctx, uint32_t& j, bool is_quoted)
inline parse_context do_one_subarg_step(arg* ret, parse_context ctx, uint32_t& j, bool is_quoted)
{
if( ctx[ctx.i] == '`' )
{
// add previous subarg
std::string tmpstr=std::string(ctx.data+j, ctx.i-j);
if(tmpstr!="")
ret->add(tmpstr);
if(ctx.i-j>0)
ret->add(std::string(ctx.data+j, ctx.i-j));
ctx.i++;
uint32_t k=skip_until(ctx, "`");
@ -451,9 +450,8 @@ parse_context do_one_subarg_step(arg* ret, parse_context ctx, uint32_t& j, bool
else if( word_eq("$((", ctx) ) // arithmetic operation
{
// add previous subarg
std::string tmpstr=std::string(ctx.data+j, ctx.i-j);
if(tmpstr!="")
ret->add(tmpstr);
if(ctx.i-j>0)
ret->add(std::string(ctx.data+j, ctx.i-j));
// get arithmetic
ctx.i+=3;
auto r=parse_arithmetic(ctx);
@ -474,9 +472,8 @@ parse_context do_one_subarg_step(arg* ret, parse_context ctx, uint32_t& j, bool
else if( word_eq("$(", ctx) ) // substitution
{
// add previous subarg
std::string tmpstr=std::string(ctx.data+j, ctx.i-j);
if(tmpstr!="")
ret->add(tmpstr);
if(ctx.i-j>0)
ret->add(std::string(ctx.data+j, ctx.i-j));
// get subshell
ctx.i+=2;
auto r=parse_subshell(ctx);
@ -487,9 +484,8 @@ parse_context do_one_subarg_step(arg* ret, parse_context ctx, uint32_t& j, bool
else if( word_eq("${", ctx) ) // variable manipulation
{
// add previous subarg
std::string tmpstr=std::string(ctx.data+j, ctx.i-j);
if(tmpstr!="")
ret->add(tmpstr);
if(ctx.i-j>0)
ret->add(std::string(ctx.data+j, ctx.i-j));
// get manipulation
ctx.i+=2;
auto r=parse_manipulation(ctx);
@ -505,9 +501,8 @@ parse_context do_one_subarg_step(arg* ret, parse_context ctx, uint32_t& j, bool
if(r.first !=nullptr)
{
// add previous subarg
std::string tmpstr=std::string(ctx.data+j, ctx.i-j);
if(tmpstr!="")
ret->add(tmpstr);
if(ctx.i-j>0)
ret->add(std::string(ctx.data+j, ctx.i-j));
// add var
ret->add(new variable_subarg(r.first, is_quoted));
ctx = r.second;
@ -521,10 +516,30 @@ parse_context do_one_subarg_step(arg* ret, parse_context ctx, uint32_t& j, bool
return ctx;
}
uint64_t find_any(parse_context const& ctx, const char* chars, uint32_t nchar) {
uint64_t lowest=ctx.size;
uint64_t trank=0;
for(uint32_t i=0; i<nchar; i++) {
const char* tc = strchr(ctx.data+ctx.i, chars[i]);
if(tc != NULL) {
trank = tc-ctx.data;
if(trank < lowest)
lowest = trank;
}
}
return lowest;
}
bool _optimize_skip_arg(parse_context& ctx, const char* str) {
while(ctx.i<ctx.size && !is_in(ctx[ctx.i], str))
ctx.i++;
return true;
}
// parse one argument
// must start at a read char
// ends at either " \t|&;\n()"
std::pair<arg*, parse_context> parse_arg(parse_context ctx, const char* end, const char* unexpected, bool doquote)
std::pair<arg*, parse_context> parse_arg(parse_context ctx, const char* end, const char* unexpected, bool doquote, const char* optimize)
{
arg* ret = new arg;
// j : start of subarg , q = start of quote
@ -535,9 +550,9 @@ std::pair<arg*, parse_context> parse_arg(parse_context ctx, const char* end, con
parse_error( unexpected_token(ctx[ctx.i]), ctx);
}
while(ctx.i<ctx.size && !(end != NULL && is_in(ctx[ctx.i], end)) )
while(ctx.i<ctx.size && _optimize_skip_arg(ctx, optimize) && !(end != NULL && is_in(ctx[ctx.i], end)) )
{
if(ctx.i+1<ctx.size && is_in(ctx[ctx.i], "<>") && ctx[ctx.i+1]=='&') // special case for <& and >&
if(ctx.i+1<ctx.size && ctx[ctx.i+1]=='&' && (ctx[ctx.i] == '<' || ctx[ctx.i] == '>')) // special case for <& and >&
{
ctx.i += 2;
}
@ -548,9 +563,8 @@ std::pair<arg*, parse_context> parse_arg(parse_context ctx, const char* end, con
break;
if(ctx[ctx.i] == '\n') // \ on \n : skip this char
{
std::string tmpstr=std::string(ctx.data+j, ctx.i-1-j);
if(tmpstr!="")
ret->add(tmpstr);
if(ctx.i-1-j>0)
ret->add(std::string(ctx.data+j, ctx.i-1-j));
ctx.i++;
j=ctx.i;
}
@ -623,7 +637,7 @@ parse_context parse_heredocument(parse_context ctx)
// std::string tmpparse=std::string(ctx.data+j, ctx.i-j);
parse_context newctx = make_context(ctx, j);
newctx.size = ctx.i;
auto pval = parse_arg(newctx , NULL, NULL, false);
auto pval = parse_arg(newctx , NULL, NULL, false, ARG_OPTIMIZE_NULL);
ctx.i = pval.second.i;
ctx.has_errored = pval.second.has_errored;
ctx.here_document->here_document = pval.first;
@ -792,8 +806,8 @@ std::pair<arglist*, parse_context> parse_arglist(parse_context ctx, bool hard_er
while(true)
{
if(ret == nullptr)
ret = new arglist;
auto pp=parse_arg(ctx, SEPARATORS, NULL);
ret = new arglist;
auto pp=parse_arg(ctx, SEPARATORS, NULL, true, ARG_OPTIMIZE_BASHTEST);
ret->add(pp.first);
ctx = pp.second;
ctx.i = skip_chars(ctx, SEPARATORS);
@ -1231,7 +1245,7 @@ parse_context parse_cmd_varassigns(cmd* in, parse_context ctx, bool cmdassign=fa
parse_error("Unallowed special assign", ctx);
}
ctx.i++;
auto pp=parse_arg(ctx, ")");
auto pp=parse_arg(ctx, ")", ARG_OPTIMIZE_DEFARR);
ta=pp.first;
ta->insert(0,"(");
ta->add(")");