folkert/simh-testsetgenerator
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

SCP: Add substring and string substitution to environment variable expansion

Browse source
This commit is contained in:
Mark Pizzolato 2018-07-14 18:29:26 -07:00
parent e2e17e1594
commit 82ea9c59ca
1 changed files with 143 additions and 1 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

144
scp.c
View file

@ -1536,7 +1536,27 @@ static const char simh_help[] =
"+then looked up as an environment variable. If found it the value is\n"
"+supstituted for the original string before expanding everything else. If\n"
"+it is not found, then the original beginning token on the line is left\n"
"+untouched.\n"
"+untouched.\n\n"
"+Environment variable string substitution:\n\n"
"++%%XYZ:str1=str2%%\n\n"
"+would expand the XYZ environment variable, substituting each occurrence\n"
"+of \"str1\" in the expanded result with \"str2\". \"str2\" can be the empty\n"
"+string to effectively delete all occurrences of \"str1\" from the expanded\n"
"+output. \"str1\" can begin with an asterisk, in which case it will match\n"
"+everything from the beginning of the expanded output to the first\n"
"+occurrence of the remaining portion of str1.\n\n"
"+May also specify substrings for an expansion.\n\n"
"++%%XYZ:~10,5%%\n\n"
"+would expand the XYZ environment variable, and then use only the 5\n"
"+characters that begin at the 11th (offset 10) character of the expanded\n"
"+result. If the length is not specified, then it defaults to the\n"
"+remainder of the variable value. If either number (offset or length) is\n"
"+negative, then the number used is the length of the environment variable\n"
"+value added to the offset or length specified.\n\n"
"++%%XYZ:~-10%%\n\n"
"+would extract the last 10 characters of the XYZ variable.\n\n"
"++%%XYZ:~0,-2%%\n\n"
"+would extract all but the last 2 characters of the XYZ variable.\n"
#define HLP_GOTO "*Commands Executing_Command_Files GOTO"
"3GOTO\n"
" Commands in a command file execute in sequence until either an error\n"
@ -3619,11 +3639,127 @@ if (ap) { /* environment variable found? */
return ap;
}
/*
Environment variable substitution:
%XYZ:str1=str2%
would expand the XYZ environment variable, substituting each occurrence
of "str1" in the expanded result with "str2". "str2" can be the empty
string to effectively delete all occurrences of "str1" from the expanded
output. "str1" can begin with an asterisk, in which case it will match
everything from the beginning of the expanded output to the first
occurrence of the remaining portion of str1.
May also specify substrings for an expansion.
%XYZ:~10,5%
would expand the XYZ environment variable, and then use only the 5
characters that begin at the 11th (offset 10) character of the expanded
result. If the length is not specified, then it defaults to the
remainder of the variable value. If either number (offset or length) is
negative, then the number used is the length of the environment variable
value added to the offset or length specified.
%XYZ:~-10%
would extract the last 10 characters of the XYZ variable.
%XYZ:~0,-2%
would extract all but the last 2 characters of the XYZ variable.
*/
static void _sim_subststr_substr (const char *ops, char *rbuf, size_t rbuf_size)
{
int rbuf_len = (int)strlen (rbuf);
char *tstr = (char *)malloc (1 + rbuf_len);
strcpy (tstr, rbuf);
if (*ops == '~') { /* Substring? */
int offset, length;
int o, l;
switch (sscanf (ops + 1, "%d,%d", &o, &l)) {
case 2:
if (l < 0)
length = rbuf_len - MIN(-l, rbuf_len);
else
length = l;
/* fall through */
case 1:
if (o < 0)
offset = rbuf_len - MIN(-o, rbuf_len);
else
offset = MIN(o, rbuf_len);
break;
case 0:
offset = 0;
length = rbuf_len;
break;
}
if (offset + length > rbuf_len)
length = rbuf_len - offset;
memcpy (rbuf, tstr + offset, length);
rbuf[length] = '\0';
}
else {
const char *eq;
if ((eq = strchr (ops, '='))) { /* Substitute? */
const char *last = tstr;
const char *curr = tstr;
char *match = (char *)malloc (1 + (eq - ops));
size_t move_size;
t_bool asterisk_match;
strlcpy (match, ops, 1 + (eq - ops));
asterisk_match = (*ops == '*');
if (asterisk_match)
memmove (match, match + 1, 1 + strlen (match + 1));
while ((curr = strstr (last, match))) {
if (!asterisk_match) {
move_size = MIN((size_t)(curr - last), rbuf_size);
memcpy (rbuf, last, move_size);
rbuf_size -= move_size;
rbuf += move_size;
}
else
asterisk_match = FALSE;
move_size = MIN(strlen (eq + 1), rbuf_size);
memcpy (rbuf, eq + 1, move_size);
rbuf_size -= move_size;
rbuf += move_size;
curr += strlen (match);
last = curr;
}
move_size = MIN(strlen (last), rbuf_size);
memcpy (rbuf, last, move_size);
rbuf_size -= move_size;
rbuf += move_size;
if (rbuf_size)
*rbuf = '\0';
}
}
free (tstr);
}
static const char *
_sim_get_env_special (const char *gbuf, char *rbuf, size_t rbuf_size)
{
const char *ap;
const char *fixup_needed = strchr (gbuf, ':');
char *tgbuf = NULL;
size_t tgbuf_size = MAX(rbuf_size, 1 + (size_t)(fixup_needed - gbuf));
if (fixup_needed) {
tgbuf = (char *)calloc (tgbuf_size, 1);
memcpy (tgbuf, gbuf, (fixup_needed - gbuf));
gbuf = tgbuf;
}
ap = _sim_gen_env_uplowcase (gbuf, rbuf, rbuf_size);/* Look for environment variable */
if (!ap) { /* no environment variable found? */
time_t now = (time_t)cmd_time.tv_sec;
@ -3788,6 +3924,12 @@ if (!ap) { /* no environment variable found? */
ap = rbuf;
}
}
if (ap && fixup_needed) { /* substring/substituted needed? */
strlcpy (tgbuf, ap, tgbuf_size);
_sim_subststr_substr (fixup_needed + 1, tgbuf, tgbuf_size);
strlcpy (rbuf, tgbuf, rbuf_size);
}
free (tgbuf);
return ap;
}