Equipped frontend_pipes_xorriso.c with word parser code

master
Thomas Schmitt 10 years ago
parent 3414e4eb78
commit 9367e43923
  1. 516
      test/frontend_pipes_xorriso.c

@ -1,6 +1,7 @@
/* Beefed-up example from man 2 pipe
to illustrate how xorriso is to be used by frontend programs via two pipes.
Additionally there is a standalone implementation of Xorriso_parse_line().
Copyright 2012 Thomas Schmitt, <scdbackup@gmx.net>
Unaltered provided under BSD license.
@ -11,7 +12,7 @@
cc -g -o frontend_pipes_xorriso frontend_pipes_xorriso.c
Usage:
./frontend_pipes_xorriso [path_to_xorriso_binary]
./frontend_pipes_xorriso [path_to_xorriso_binary | -h]
*/
@ -21,11 +22,34 @@
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <ctype.h>
/* Local helpers of parent process */
int await_all_replies(int fd, char *pending_mark);
int prompt_for_command(char *line, int line_size);
struct parse_rules { /* Parsing_parameters. See xorriso.h Xorriso_parse_line */
int do_parse;
char progname[1024];
char prefix[1024];
char separators[256];
int max_words;
int flag;
};
int parse_line(char *progname, char *line,
char *prefix, char *separators, int max_words,
int *argc, char ***argv, int flag);
int dispose_parsed_words(int *argc, char ***argv);
static int await_all_replies(int fd, char *pending_mark,
struct parse_rules *parse);
static int prompt_for_command(char *line, int line_size,
struct parse_rules *parse);
static int usage();
/* Parent and child */
@ -35,8 +59,14 @@ int main(int argc, char *argv[])
pid_t cpid;
char *xorriso_path = "/usr/bin/xorriso";
if (argc > 1)
if (argc > 1) {
if (strcmp(argv[1], "-h") == 0 || strcmp(argv[1], "-help") == 0 ||
strcmp(argv[1], "--help") == 0) {
usage();
exit(0);
}
xorriso_path = argv[1];
}
if (pipe(command_pipe) == -1)
{ perror("pipe"); exit(1); }
@ -82,21 +112,25 @@ int main(int argc, char *argv[])
int mark_count = 0, ret;
char pending_mark[16], line[4096];
struct parse_rules parse;
close(command_pipe[0]); /* Close unused read end */
close(reply_pipe[1]); /* Close unused write end */
memset(&parse, 0, sizeof(parse)); /* Disable parsing as default */
strcpy(parse.progname, argv[0]);
/* Dialog loop */
sprintf(pending_mark, "%d", mark_count);
while (1) {
/* Wait for pending mark and print all replies */
ret = await_all_replies(reply_pipe[0], pending_mark);
ret = await_all_replies(reply_pipe[0], pending_mark, &parse);
if (ret < 0)
break;
/* Prompt for command line */
ret = prompt_for_command(line, sizeof(line));
ret = prompt_for_command(line, sizeof(line), &parse);
if (ret <= 0)
break;
@ -130,10 +164,60 @@ int main(int argc, char *argv[])
}
/* Local helpers of parent process */
/* ------------------- Local helpers of parent process -------------------- */
static int usage()
{
static char helptext[][80] = {
"usage: frontend_pipes_xorriso [path_to_xorriso|-h]",
"",
"Forks a process that runs xorriso and communicates with it via two pipes.",
"The command pipe sends payload commands and -mark commands. The reply pipe",
"receives -pkt_output lines which it dispatches to stdout and stderr.",
"The communication between both processes is made synchronous by the parent",
"awaiting the -mark message of the child.",
"Optionally the reply lines can be parsed into words. This is initiated by",
"meta command",
" @parse [prefix [separators [max_words [flag]]]]",
"which sets the four parameters for a function equivalent to",
"Xorriso_parse_line() (see xorriso.h). All reply will then be parsed and",
"non-empty word arrays are displayed. Meta command",
" @noparse",
"ends this mode.",
"@END@"
};
int i;
for (i = 0; strcmp(helptext[i], "@END@") != 0; i++)
fprintf(stderr, "%s\n", helptext[i]);
return(1);
}
static int show_parsed(struct parse_rules *parse, char *line)
{
int argc, ret = 0, i;
char **argv = NULL;
if (!parse->do_parse)
return(2);
ret = parse_line(parse->progname, line, parse->prefix, parse->separators,
parse->max_words, &argc, &argv, parse->flag);
if (ret <= 0 || argc <= 0)
return(0);
fprintf(stderr, "-----------------------------------------------------\n");
fprintf(stderr, "parse_line returns %d, argc = %d\n", ret, argc);
for (i = 0; i < argc; i++)
fprintf(stderr, "%2d : %s\n", i, argv[i]);
fprintf(stderr, "-----------------------------------------------------\n");
dispose_parsed_words(&argc, &argv); /* release memory */
return(1);
}
int await_all_replies(int fd, char *pending_mark)
static int await_all_replies(int fd, char *pending_mark,
struct parse_rules *parse)
{
int count, remainder = 0;
char buf[32769], *line, *npt;
@ -206,6 +290,11 @@ int await_all_replies(int fd, char *pending_mark)
*/
fprintf(stderr, "%s\n", line);
}
/* Parse line and show words */
if (strlen(line) >= 5)
show_parsed(parse, line + 5);
line = npt + 1;
}
}
@ -213,23 +302,408 @@ int await_all_replies(int fd, char *pending_mark)
}
int prompt_for_command(char *line, int line_size)
static int input_interpreter(char *line, struct parse_rules *parse)
{
int l;
char *line_res;
int argc, ret = 0;
char **argv = NULL;
fprintf(stderr, "+++ Enter a command and its parameters :\n");
line_res = fgets(line, line_size - 1, stdin);
if (line_res == NULL)
ret = parse_line(parse->progname, line, "", "", 6, &argc, &argv, 0);
if (ret <= 0 || argc <= 0)
return(0);
l = strlen(line);
if (l == 0) {
line[0] = '\n';
line[1] = 0;
} else if (line[l - 1] != '\n') {
line[l] = '\n';
line[l + 1] = 0;
if (strcmp(argv[0], "@parse") == 0) {
parse->do_parse = 1;
parse->prefix[0] = 0;
if (argc > 1)
strcpy(parse->prefix, argv[1]);
parse->separators[0] = 0;
if (argc > 2)
strcpy(parse->separators, argv[2]);
parse->max_words = 0;
if (argc > 3)
sscanf(argv[3], "%d", &(parse->max_words));
parse->max_words = 0;
if (argc > 4)
sscanf(argv[4], "%d", &(parse->flag));
ret = 1;
} else if(strcmp(argv[0], "@noparse") == 0) {
parse->do_parse = 0;
ret = 1;
} else {
ret = 0;
}
dispose_parsed_words(&argc, &argv); /* release memory */
return ret;
}
static int prompt_for_command(char *line, int line_size,
struct parse_rules *parse)
{
int l, ret;
char *line_res;
while (1) {
fprintf(stderr, "+++ Enter a command and its parameters :\n");
line_res = fgets(line, line_size - 1, stdin);
if (line_res == NULL)
return(0);
l = strlen(line);
if (l == 0) {
line[0] = '\n';
line[1] = 0;
} else if (line[l - 1] != '\n') {
line[l] = '\n';
line[l + 1] = 0;
}
/* Interpret meta commands which begin by @ */
ret = input_interpreter(line, parse);
if (ret == 0)
return(1);
if (ret < 0)
return(-1);
}
}
/* -------- Line-to-word parser equivalent to Xorriso_parse_line() -------- */
static int Sfile_sep_make_argv(char *progname, char *line, char *separators,
int max_words, int *argc, char ***argv, int flag);
int parse_line(char *progname, char *line,
char *prefix, char *separators, int max_words,
int *argc, char ***argv, int flag)
{
int ret, bsl_mode;
char *to_parse;
*argc = 0;
*argv = NULL;
to_parse = line;
bsl_mode = (flag >> 1) & 15;
if (prefix[0]) {
if (strncmp(line, prefix, strlen(prefix)) == 0) {
to_parse = line + strlen(prefix);
} else {
ret = 2; goto ex;
}
}
ret = Sfile_sep_make_argv(progname, to_parse, separators,
max_words, argc, argv,
(!(flag & 32)) | 4 | (bsl_mode << 5));
if (ret < 0) {
fprintf(stderr,
"%s : Severe lack of resources during command line parsing\n",
progname);
goto ex;
}
if (ret == 0) {
fprintf(stderr,
"%s : Incomplete quotation in %s line: %s\n",
progname, (flag & 32) ? "command" : "parsed", to_parse);
goto ex;
}
ex:;
if (ret <= 0)
Sfile_sep_make_argv("", "", "", 0, argc, argv, 2); /* release memory */
return(ret);
}
int dispose_parsed_words(int *argc, char ***argv)
{
Sfile_sep_make_argv("", "", "", 0, argc, argv, 2);
return(1);
}
/* -------------- Some helpers copied from xorriso/sfile.c ----------------- */
static int Sfile_destroy_argv(int *argc, char ***argv, int flag)
{
int i;
if(*argc>0 && *argv!=NULL){
for(i=0;i<*argc;i++){
if((*argv)[i]!=NULL)
free((*argv)[i]);
}
free((char *) *argv);
}
*argc= 0;
*argv= NULL;
return(1);
}
/* Converts backslash codes into single characters:
\a BEL 7 , \b BS 8 , \e ESC 27 , \f FF 12 , \n LF 10 , \r CR 13 ,
\t HT 9 , \v VT 11 , \\ \ 92
\[0-9][0-9][0-9] octal code , \x[0-9a-f][0-9a-f] hex code ,
\cX control-x (ascii(X)-64)
@param upto maximum number of characters to examine for backslash.
The scope of a backslash (0 to 3 characters) is not affected.
@param eaten returns the difference in length between input and output
@param flag bit0= only determine *eaten, do not convert
bit1= allow to convert \000 to binary 0
*/
static int Sfile_bsl_interpreter(char *text, int upto, int *eaten, int flag)
{
char *rpt, *wpt, num_text[8], wdummy[8];
unsigned int num= 0;
*eaten= 0;
wpt= text;
for(rpt= text; *rpt != 0 && rpt - text < upto; rpt++) {
if(flag & 1)
wpt= wdummy;
if(*rpt == '\\') {
rpt++;
(*eaten)++;
if(*rpt == 'a') {
*(wpt++)= 7;
} else if(*rpt == 'b') {
*(wpt++)= 8;
} else if(*rpt == 'e') {
*(wpt++)= 27;
} else if(*rpt == 'f') {
*(wpt++)= 12;
} else if(*rpt == 'n') {
*(wpt++)= 10;
} else if(*rpt == 'r') {
*(wpt++)= 13;
} else if(*rpt == 't') {
*(wpt++)= 9;
} else if(*rpt == 'v') {
*(wpt++)= 11;
} else if(*rpt == '\\') {
*(wpt++)= '\\';
} else if(rpt[0] >= '0' && rpt[0] <= '7' &&
rpt[1] >= '0' && rpt[1] <= '7' &&
rpt[2] >= '0' && rpt[2] <= '7') {
num_text[0]= '0';
num_text[1]= *(rpt + 0);
num_text[2]= *(rpt + 1);
num_text[3]= *(rpt + 2);
num_text[4]= 0;
sscanf(num_text, "%o", &num);
if((num > 0 || (flag & 2)) && num <= 255) {
rpt+= 2;
(*eaten)+= 2;
*(wpt++)= num;
} else
goto not_a_code;
} else if(rpt[0] == 'x' &&
((rpt[1] >= '0' && rpt[1] <= '9') ||
(rpt[1] >= 'A' && rpt[1] <= 'F') ||
(rpt[1] >= 'a' && rpt[1] <= 'f'))
&&
((rpt[2] >= '0' && rpt[2] <= '9') ||
(rpt[2] >= 'A' && rpt[2] <= 'F') ||
(rpt[2] >= 'a' && rpt[2] <= 'f'))
) {
num_text[0]= *(rpt + 1);
num_text[1]= *(rpt + 2);
num_text[2]= 0;
sscanf(num_text, "%x", &num);
if(num > 0 && num <= 255) {
rpt+= 2;
(*eaten)+= 2;
*(wpt++)= num;
} else
goto not_a_code;
} else if(*rpt == 'c') {
if(rpt[1] > 64 && rpt[1] < 96) {
*(wpt++)= rpt[1] - 64;
rpt++;
(*eaten)++;
} else
goto not_a_code;
} else {
not_a_code:;
*(wpt++)= '\\';
rpt--;
(*eaten)--;
}
} else
*(wpt++)= *rpt;
}
*wpt= *rpt;
return(1);
}
#define SfileadrL 4096
static int Sfile_sep_make_argv(char *progname, char *line, char *separators,
int max_words, int *argc, char ***argv, int flag)
/*
bit0= read progname as first argument from line
bit1= just release argument list argv and return
bit2= abort with return(0) if incomplete quotes are found
bit3= eventually prepend missing '-' to first argument read from line
bit4= like bit2 but only check quote completeness, do not allocate memory
bit5+6= interpretation of backslashes:
0= no interpretation, leave unchanged
1= only inside double quotes
2= outside single quotes
3= everywhere
bit7= append a NULL element to argv
*/
{
int i,pass,maxl=0,l,argzaehl=0,bufl,line_start_argc, bsl_mode, ret= 0, eaten;
char *cpt,*start;
char *buf= NULL;
Sfile_destroy_argv(argc,argv,0);
if(flag&2)
{ret= 1; goto ex;}
if(flag & 16)
flag|= 4;
bsl_mode= (flag >> 5) & 3;
buf= calloc(strlen(line) + SfileadrL, 1);
if(buf == NULL)
{ret= -1; goto ex;}
for(pass=0;pass<2;pass++) {
cpt= line-1;
if(!(flag&1)){
argzaehl= line_start_argc= 1;
if(pass==0)
maxl= strlen(progname);
else
strcpy((*argv)[0],progname);
} else {
argzaehl= line_start_argc= 0;
if(pass==0) maxl= 0;
}
while(*(++cpt)!=0){
if(*separators) {
if(strchr(separators, *cpt) != NULL)
continue;
} else if(isspace(*cpt))
continue;
start= cpt;
buf[0]= 0;
cpt--;
if(max_words > 0 && argzaehl >= max_words && *cpt != 0) {
/* take uninterpreted up to the end */
cpt+= strlen(cpt) - 1;
}
while(*(++cpt)!=0) {
if(*separators) {
if(strchr(separators, *cpt) != NULL)
break;
} else if(isspace(*cpt))
break;
if(*cpt=='"'){
l= cpt-start; bufl= strlen(buf);
if(l>0) {
strncpy(buf + bufl, start, l); buf[bufl + l]= 0;
if(bsl_mode >= 3) {
ret= Sfile_bsl_interpreter(buf, l, &eaten, 0);
if(ret <= 0)
goto ex;
}
}
l= strlen(buf);
start= cpt+1;
while(*(++cpt)!=0) if(*cpt=='"') break;
if((flag&4) && *cpt==0)
{ret= 0; goto ex;}
l= cpt-start; bufl= strlen(buf);
if(l>0) {
strncpy(buf + bufl, start, l);
buf[bufl + l]= 0;
if(bsl_mode >= 1) {
ret= Sfile_bsl_interpreter(buf + bufl, l, &eaten, 0);
if(ret <= 0)
goto ex;
}
}
start= cpt+1;
}else if(*cpt=='\''){
l= cpt-start; bufl= strlen(buf);
if(l>0) {
strncpy(buf + bufl, start, l); buf[bufl + l]= 0;
if(bsl_mode >= 3) {
ret= Sfile_bsl_interpreter(buf, l, &eaten, 0);
if(ret <= 0)
goto ex;
}
}
l= strlen(buf);
start= cpt+1;
while(*(++cpt)!=0) if(*cpt=='\'') break;
if((flag&4) && *cpt==0)
{ret= 0; goto ex;}
l= cpt-start; bufl= strlen(buf);
if(l>0) {
strncat(buf,start,l);buf[bufl+l]= 0;
if(bsl_mode >= 2) {
ret= Sfile_bsl_interpreter(buf + bufl, l, &eaten, 0);
if(ret <= 0)
goto ex;
}
}
start= cpt+1;
}
if(*cpt==0) break;
}
l= cpt-start;
bufl= strlen(buf);
if(l>0) {
strncpy(buf + bufl, start, l); buf[bufl + l]= 0;
if(bsl_mode >= 3) {
ret= Sfile_bsl_interpreter(buf, l, &eaten, 0);
if(ret <= 0)
goto ex;
}
}
l= strlen(buf);
if(pass==0){
if(argzaehl==line_start_argc && (flag&8))
if(buf[0]!='-' && buf[0]!=0 && buf[0]!='#')
l++;
if(l>maxl) maxl= l;
}else{
strcpy((*argv)[argzaehl],buf);
if(argzaehl==line_start_argc && (flag&8))
if(buf[0]!='-' && buf[0]!=0 && buf[0]!='#')
sprintf((*argv)[argzaehl],"-%s", buf);
}
argzaehl++;
if(*cpt==0) break;
}
if(pass==0){
if(flag & 16)
{ret= 1; goto ex;}
*argc= argzaehl;
if(argzaehl>0 || (flag & 128)) {
*argv= (char **) calloc((argzaehl + !!(flag & 128)), sizeof(char *));
if(*argv==NULL)
{ret= -1; goto ex;}
}
for(i=0;i<*argc;i++) {
(*argv)[i]= (char *) calloc(maxl + 1, 1);
if((*argv)[i]==NULL)
{ret= -1; goto ex;}
}
if(flag & 128)
(*argv)[*argc]= NULL;
}
}
ret= 1;
ex:
if(buf != NULL)
free(buf);
return(ret);
}

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