diff options
| -rw-r--r-- | txr.1 | 107 | ||||
| -rw-r--r-- | txr.c | 61 |
2 files changed, 150 insertions, 18 deletions
@@ -42479,6 +42479,113 @@ running with setuid privilege. No group IDs are added to the list which need to be retracted when privileges are dropped. The supplementary groups also persist across the execution of a setuid/setgid script. +.SH* STAND-ALONE APPLICATION SUPPORT + +The \*(TX executable image supports a general mechanism by means of which +a custom program can be packaged as an apparent stand-alone executable. + +.SS* The Internal Argument String + +The \*(TX executable contains a 128 byte data area preceded by the +seven-byte ASCII character sequence +.strn @(txr): . +The 128 byte data area which follows this identifying prefix +represents a null-terminated UTF-8 string. In the stock executable, +this area is filled with null bytes. + +If the \*(TX executable is edited such that this area is replaced +with a non-empty, null-terminated UTF-8 string, the program will, +for the purposes of command line argument processing, treat this string as if +it were the one and only command line argument. (The original command +line arguments are still retained in the +.code *args* +and +.code *args-full* +variables). + +.TP* Example: + +Suppose that \*(TX is copied to an executable in the same directory called +.code myapp +(or +.code myapp.exe +on an operating system which requires the +.code .exe +suffix). Also suppose that in the same directory, there exists a file +called +.codn myscript.tl . + +This +.code myapp +executable can then be edited so that the data area which follows the +.code @(txr): +bytes contains the following string: + +.cblk + --args|-e|(load `@{txr-path}/main.tl`) +.cble + +When the +.code myapp +executable is invoked, it will process the above string as a single +command line argument, causing the +.code main.tl +\*(TL source file to be loaded. +Any arguments passed to +.code myapp +are ignored and available to +.code main.tl +via the +.code *args* +variable. + +.SS* Deployment Directory Structure + +The \*(TX executable may require library files, depending on the +functionality invoked by the program code. Library files are located +relative to the installation directory, called the +.IR sysroot . +The executable tries to dynamically determine the sysroot from +its own location, according to this directory structure: + +.cblk + /path/to/sysroot/bin/txr + .../share/txr/stdlib/cadr.tl + .../stdlib/except.tl + ... +.cble + +The above structure is assumed if the executable finds itself +in a directory named +.strn bin . + +Otherwise, if the executable finds itself in a directory not +named +.strn bin , +the following structure is expected: + +.cblk + /path/to/installation/txr + .../share/txr/stdlib/cadr.tl + .../share/txr/stdlib/except.tl + ... +.cble + +When a custom application is deployed using a possibly renamed +.code txr +executable, one of the above structures should be observed: +either the sysroot with a +.code bin +subdirectory where the executable is located, on the +same level with the +.code share +directory, or else the second structure in which the +.code share +directory is a subdirectory of the executable directory. +If one of these structures is not observed, the application +may fail due to the failure of a library file to load. + + .SH* DEBUGGER \*(TX has a simple, crude, built-in debugger. The debugger is invoked by adding the @@ -295,6 +295,8 @@ static val sysroot(val target) static void sysroot_init(void) { + val prog_dir; + #if HAVE_WINDOWS_H val slash = regex_compile(lit("\\\\"), nil); #endif @@ -303,6 +305,7 @@ static void sysroot_init(void) #if HAVE_WINDOWS_H prog_path = regsub(slash, lit("/"), prog_path); #endif + prog_dir = dirname(prog_path); if (!(maybe_sysroot(lit(TXR_REL_PATH)) || maybe_sysroot(lit(TXR_REL_PATH EXE_SUFF)) || @@ -310,9 +313,7 @@ static void sysroot_init(void) maybe_sysroot(lit(PROG_NAME EXE_SUFF)) || maybe_sysroot(substitute_basename(lit(TXR_REL_PATH), prog_path)))) { - format(std_error, lit("~a: unable to calculate sysroot\n"), - prog_string, nao); - sysroot_path = lit(""); + sysroot_path = prog_dir; } stdlib_path = sysroot(lit("share/txr/stdlib")); @@ -322,7 +323,7 @@ static void sysroot_init(void) toint(lit(TXR_VER), nil)); reg_varl(intern(lit("txr-version"), user_package), toint(lit(TXR_VER), nil)); - reg_varl(intern(lit("txr-path"), user_package), dirname(prog_path)); + reg_varl(intern(lit("txr-path"), user_package), prog_dir); } static int license(void) @@ -438,6 +439,7 @@ static void no_dbg_support(val arg) int txr_main(int argc, char **argv) { + uses_or2; val specstring = nil; val spec = nil; val spec_file = nil; @@ -453,8 +455,11 @@ int txr_main(int argc, char **argv) val self_path_s = intern(lit("self-path"), user_package); val compat_var = lit("TXR_COMPAT"); val compat_val = getenv_wrap(compat_var); + val orig_args = nil; list_collect_decl(arg_list, arg_tail); + static char alt_args_buf[128 + 7] = "@(txr):", *alt_args = alt_args_buf + 7; + setvbuf(stderr, 0, _IOLBF, 0); if (compat_val && length(compat_val) != zero) { @@ -480,7 +485,10 @@ int txr_main(int argc, char **argv) arg_list = cdr(arg_list); - if (argc <= 1) { + if (*alt_args) { + orig_args = arg_list; + arg_list = list(string_utf8(alt_args), nao); + } else if (argc <= 1) { drop_privilege(); #if HAVE_TERMIOS banner(); @@ -710,32 +718,49 @@ int txr_main(int argc, char **argv) break; case 'e': drop_privilege(); - reg_varl(self_path_s, lit("cmdline-expr")); - reg_var(args_s, arg_list); - - eval_intrinsic(lisp_parse(arg, std_error, colon_k, - lit("cmdline-expr"), colon_k), - make_env(bindings, nil, nil)); - evaled = t; - arg_list = cdr(lookup_global_var(args_s)); + { + val args_saved = or2(orig_args, arg_list); + val args_new; + + reg_varl(self_path_s, lit("cmdline-expr")); + reg_var(args_s, or2(orig_args, arg_list)); + + eval_intrinsic(lisp_parse(arg, std_error, colon_k, + lit("cmdline-expr"), colon_k), + make_env(bindings, nil, nil)); + evaled = t; + args_new = cdr(lookup_global_var(args_s)); + + if (args_new != args_saved) { + arg_list = args_new; + orig_args = nil; + } + } break; case 'p': case 'P': case 't': + drop_privilege(); { val (*pf)(val obj, val out) = if3(c_chr(opt) == 'p', prinl, if3(c_chr(opt) == 'P', pprinl, tprint)); - drop_privilege(); + val args_saved = or2(orig_args, arg_list); + val args_new; + reg_varl(self_path_s, lit("cmdline-expr")); - reg_var(args_s, arg_list); + reg_var(args_s, or2(orig_args, arg_list)); pf(eval_intrinsic(lisp_parse(arg, std_error, colon_k, lit("cmdline-expr"), colon_k), make_env(bindings, nil, nil)), std_output); evaled = t; - arg_list = cdr(lookup_global_var(args_s)); + args_new = cdr(lookup_global_var(args_s)); + if (args_new != args_saved) { + arg_list = args_new; + orig_args = nil; + } } break; } @@ -871,7 +896,7 @@ int txr_main(int argc, char **argv) } } - reg_var(args_s, arg_list); + reg_var(args_s, or2(orig_args, arg_list)); reg_varl(intern(lit("self-path"), user_package), spec_file_str); if (!txr_lisp_p) @@ -926,7 +951,7 @@ repl: lit("Note: operating in TXR ~a compatibility mode " "due to environment variable.\n"), num(opt_compat), nao); - reg_var(args_s, arg_list); + reg_var(args_s, or2(orig_args, arg_list)); reg_varl(intern(lit("self-path"), user_package), lit("listener")); repl(bindings, std_input, std_output); #endif |