OpenBSD-4.6/gnu/usr.bin/lynx/src/LYExtern.c
/*
External application support.
This feature allows lynx to pass a given URL to an external program.
It was written for three reasons.
1) To overcome the deficiency of Lynx_386 not supporting ftp and news.
External programs can be used instead by passing the URL.
2) To allow for background transfers in multitasking systems.
I use wget for http and ftp transfers via the external command.
3) To allow for new URLs to be used through lynx.
URLs can be made up such as mymail: to spawn desired applications
via the external command.
See lynx.cfg for other info.
*/
#include <LYUtils.h>
#ifdef USE_EXTERNALS
#include <HTAlert.h>
#include <LYGlobalDefs.h>
#include <LYExtern.h>
#include <LYLeaks.h>
#include <LYCurses.h>
#include <LYReadCFG.h>
#include <LYStrings.h>
#ifdef WIN_EX
/* ASCII char -> HEX digit */
#define ASC2HEXD(x) (((x) >= '0' && (x) <= '9') ? \
((x) - '0') : (toupper(x) - 'A' + 10))
/* Decodes the forms %xy in a URL to the character the hexadecimal
code of which is xy. xy are hexadecimal digits from
[0123456789ABCDEF] (case-insensitive). If x or y are not hex-digits
or '%' is near '\0', the whole sequence is inserted literally. */
static char *decode_string(char *s)
{
char *save_s;
char *p = s;
save_s = s;
for (; *s; s++, p++) {
if (*s != '%')
*p = *s;
else {
/* Do nothing if at the end of the string. Or if the chars
are not hex-digits. */
if (!*(s + 1) || !*(s + 2)
|| !(isxdigit(*(s + 1)) && isxdigit(*(s + 2)))) {
*p = *s;
continue;
}
*p = (char) ((ASC2HEXD(*(s + 1)) << 4) + ASC2HEXD(*(s + 2)));
s += 2;
}
}
*p = '\0';
return save_s;
}
#endif /* WIN_EX */
#ifdef WIN_EX
/*
* Quote the path to make it safe for shell command processing.
* We always quote it not only includes spaces in it.
* At least we should quote paths which include "&".
*/
char *quote_pathname(char *pathname)
{
char *result = NULL;
HTSprintf0(&result, "\"%s\"", pathname);
return result;
}
/*
* Delete dangerous characters as local path.
* We delete '<>|' and also '%"'.
* '%' should be deleted because it's difficut to escape for all cases.
* So we can't treat paths which include '%'.
* '"' should be deleted because it's a obstacle to quote whole path.
*/
static void delete_danger_characters(char *src)
{
char *dst;
for (dst = src; *src != '\0'; src++) {
if (strchr("<>|%\"", *src) == NULL) {
*dst = *src;
dst++;
}
}
*dst = '\0';
}
static char *escapeParameter(CONST char *parameter)
{
size_t i;
size_t last = strlen(parameter);
size_t n = 0;
size_t encoded = 0;
size_t escaped = 0;
char *result;
char *needs_encoded = "<>|";
char *needs_escaped = "%";
char *needs_escaped_NT = "%&^";
for (i = 0; i < last; ++i) {
if (strchr(needs_encoded, parameter[i]) != NULL) {
++encoded;
}
if (system_is_NT) {
if (strchr(needs_escaped_NT, parameter[i]) != NULL) {
++escaped;
}
} else if (strchr(needs_escaped, parameter[i]) != NULL) {
++escaped;
}
}
result = (char *) malloc(last + encoded * 2 + escaped + 1);
if (result == NULL)
outofmem(__FILE__, "escapeParameter");
n = 0;
for (i = 0; i < last; i++) {
if (strchr(needs_encoded, parameter[i]) != NULL) {
sprintf(result + n, "%%%02X", (unsigned char) parameter[i]);
n += 3;
continue;
}
if (system_is_NT) {
if (strchr(needs_escaped_NT, parameter[i]) != NULL) {
result[n++] = '^';
result[n++] = parameter[i];
continue;
}
} else if (strchr(needs_escaped, parameter[i]) != NULL) {
result[n++] = '%'; /* parameter[i] is '%' */
result[n++] = parameter[i];
continue;
}
result[n++] = parameter[i];
}
result[n] = '\0';
return result;
}
#endif /* WIN_EX */
static void format(char **result,
char *fmt,
char *parm)
{
*result = NULL;
HTAddParam(result, fmt, 1, parm);
HTEndParam(result, fmt, 1);
}
/*
* Format the given command into a buffer, returning the resulting string.
*
* It is too dangerous to leave any URL that may come along unquoted. They
* often contain '&', ';', and '?' chars, and who knows what else may occur.
* Prevent spoofing of the shell. Dunno how this needs to be modified for VMS
* or DOS. - kw
*/
static char *format_command(char *command,
char *param)
{
char *cmdbuf = NULL;
#if defined(WIN_EX)
char pram_string[LY_MAXPATH];
char *escaped = NULL;
if (strnicmp("file://localhost/", param, 17) == 0) {
/* decode local path parameter for programs to be
able to interpret - TH */
LYstrncpy(pram_string, param, sizeof(pram_string) - 1);
decode_string(pram_string);
param = pram_string;
} else {
/* encode or escape URL parameter - TH */
escaped = escapeParameter(param);
param = escaped;
}
if (isMAILTO_URL(param)) {
format(&cmdbuf, command, param + 7);
} else if (strnicmp("telnet://", param, 9) == 0) {
char host[sizeof(pram_string)];
int last_pos;
LYstrncpy(host, param + 9, sizeof(host));
last_pos = strlen(host) - 1;
if (last_pos > 1 && host[last_pos] == '/')
host[last_pos] = '\0';
format(&cmdbuf, command, host);
} else if (strnicmp("file://localhost/", param, 17) == 0) {
char e_buff[LY_MAXPATH], *p;
p = param + 17;
delete_danger_characters(p);
*e_buff = 0;
if (strchr(p, ':') == NULL) {
sprintf(e_buff, "%.3s/", windows_drive);
}
strncat(e_buff, p, sizeof(e_buff) - strlen(e_buff) - 1);
p = strrchr(e_buff, '.');
if (p) {
trimPoundSelector(p);
}
/* Less ==> short filename with backslashes,
* less ==> long filename with forward slashes, may be quoted
*/
if (ISUPPER(command[0])) {
char *short_name = HTDOS_short_name(e_buff);
p = quote_pathname(short_name);
format(&cmdbuf, command, p);
FREE(p);
} else {
p = quote_pathname(e_buff);
format(&cmdbuf, command, p);
FREE(p);
}
} else {
format(&cmdbuf, command, param);
}
FREE(escaped);
#else
format(&cmdbuf, command, param);
#endif
return cmdbuf;
}
/*
* Find the EXTERNAL command which matches the given name 'param'. If there is
* more than one possibility, make a popup menu of the matching commands and
* allow the user to select one. Return the selected command.
*/
static char *lookup_external(char *param,
BOOL only_overriders)
{
int pass, num_disabled, num_matched, num_choices, cur_choice;
int length = 0;
char *cmdbuf = NULL;
char **choices = 0;
lynx_list_item_type *ptr = 0;
for (pass = 0; pass < 2; pass++) {
num_disabled = 0;
num_matched = 0;
num_choices = 0;
for (ptr = externals; ptr != 0; ptr = ptr->next) {
if (match_item_by_name(ptr, param, only_overriders)) {
++num_matched;
CTRACE((tfp, "EXTERNAL: '%s' <==> '%s'\n", ptr->name, param));
if (no_externals && !ptr->always_enabled && !only_overriders) {
++num_disabled;
} else {
if (pass == 0) {
length++;
} else if (pass != 0) {
cmdbuf = format_command(ptr->command, param);
if (length > 1)
choices[num_choices] = cmdbuf;
}
num_choices++;
}
}
}
if (length > 1) {
if (pass == 0) {
choices = typecallocn(char *, length + 1);
} else {
choices[num_choices] = 0;
}
}
}
if (num_disabled != 0
&& num_disabled == num_matched) {
HTUserMsg(EXTERNALS_DISABLED);
} else if (num_choices > 1) {
int old_y, old_x;
LYGetYX(old_y, old_x);
cur_choice = LYhandlePopupList(-1,
0,
old_x,
(const char **) choices,
-1,
-1,
FALSE,
TRUE,
FALSE);
wmove(LYwin, old_y, old_x);
CTRACE((tfp, "selected choice %d of %d\n", cur_choice, num_choices));
if (cur_choice < 0) {
HTInfoMsg(CANCELLED);
cmdbuf = 0;
}
for (pass = 0; choices[pass] != 0; pass++) {
if (pass == cur_choice) {
cmdbuf = choices[pass];
} else {
FREE(choices[pass]);
}
}
FREE(choices);
}
return cmdbuf;
}
BOOL run_external(char *param,
BOOL only_overriders)
{
#ifdef WIN_EX
int status;
#endif
int redraw_flag = TRUE;
char *cmdbuf = NULL;
BOOL found = FALSE;
int confirmed = TRUE;
if (externals == NULL)
return 0;
#ifdef WIN_EX /* 1998/01/26 (Mon) 09:16:13 */
if (param == NULL) {
HTInfoMsg(gettext("External command is null"));
return 0;
}
#endif
cmdbuf = lookup_external(param, only_overriders);
if (non_empty(cmdbuf)) {
#ifdef WIN_EX /* 1997/10/17 (Fri) 14:07:50 */
int len;
char buff[LY_MAXPATH];
CTRACE((tfp, "Lynx EXTERNAL: '%s'\n", cmdbuf));
#ifdef WIN_GUI /* 1997/11/06 (Thu) 14:17:15 */
confirmed = MessageBox(GetForegroundWindow(), cmdbuf,
"Lynx (EXTERNAL COMMAND EXEC)",
MB_ICONQUESTION | MB_SETFOREGROUND | MB_OKCANCEL)
!= IDCANCEL;
#else
confirmed = HTConfirm(LYElideString(cmdbuf, 40)) != NO;
#endif
if (confirmed) {
len = strlen(cmdbuf);
if (len > 255) {
sprintf(buff, "Lynx: command line too long (%d > 255)", len);
#ifdef WIN_GUI /* 1997/11/06 (Thu) 14:17:02 */
MessageBox(GetForegroundWindow(), buff,
"Lynx (EXTERNAL COMMAND EXEC)",
MB_ICONEXCLAMATION | MB_SETFOREGROUND | MB_OK);
SetConsoleTitle("Lynx for Win32");
#else
HTConfirm(LYElideString(buff, 40));
#endif
confirmed = FALSE;
} else {
SetConsoleTitle(cmdbuf);
}
}
if (strnicmp(cmdbuf, "start ", 6) == 0)
redraw_flag = FALSE;
else
redraw_flag = TRUE;
#else
HTUserMsg(cmdbuf);
#endif
found = TRUE;
if (confirmed) {
if (redraw_flag) {
stop_curses();
fflush(stdout);
}
/* command running. */
#ifdef WIN_EX /* 1997/10/17 (Fri) 14:07:50 */
#if defined(__CYGWIN__) || defined(__MINGW32__)
status = system(cmdbuf);
#else
status = xsystem(cmdbuf);
#endif
if (status != 0) {
sprintf(buff,
"EXEC code = %04x (%2d, %2d)\r\n"
"'%s'",
status, (status / 256), (status & 0xff),
cmdbuf);
#ifdef SH_EX /* WIN_GUI for ERROR only */
MessageBox(GetForegroundWindow(), buff,
"Lynx (EXTERNAL COMMAND EXEC)",
MB_ICONSTOP | MB_SETFOREGROUND | MB_OK);
#else
HTConfirm(LYElideString(buff, 40));
#endif /* 1 */
}
#else /* Not WIN_EX */
LYSystem(cmdbuf);
#endif /* WIN_EX */
#if defined(WIN_EX)
SetConsoleTitle("Lynx for Win32");
#endif
if (redraw_flag) {
fflush(stdout);
start_curses();
}
}
}
FREE(cmdbuf);
return found;
}
#endif /* USE_EXTERNALS */