Exemplo n.º 1
0
static char *
evalvar(char *p, int flag)
{
	int subtype;
	int varflags;
	char *var;
	char *val;
	int patloc;
	int c;
	int set;
	int special;
	int startloc;
	int varlen;
	int varlenb;
	int easy;
	int quotes = flag & (EXP_FULL | EXP_CASE | EXP_REDIR);

	varflags = (unsigned char)*p++;
	subtype = varflags & VSTYPE;
	var = p;
	special = 0;
	if (! is_name(*p))
		special = 1;
	p = strchr(p, '=') + 1;
again: /* jump here after setting a variable with ${var=text} */
	if (varflags & VSLINENO) {
		set = 1;
		special = 0;
		val = var;
		p[-1] = '\0';	/* temporarily overwrite '=' to have \0
				   terminated string */
	} else if (special) {
		set = varisset(var, varflags & VSNUL);
		val = NULL;
	} else {
		val = bltinlookup(var, 1);
		if (val == NULL || ((varflags & VSNUL) && val[0] == '\0')) {
			val = NULL;
			set = 0;
		} else
			set = 1;
	}
	varlen = 0;
	startloc = expdest - stackblock();
	if (!set && uflag && *var != '@' && *var != '*') {
		switch (subtype) {
		case VSNORMAL:
		case VSTRIMLEFT:
		case VSTRIMLEFTMAX:
		case VSTRIMRIGHT:
		case VSTRIMRIGHTMAX:
		case VSLENGTH:
			error("%.*s: parameter not set", (int)(p - var - 1),
			    var);
		}
	}
	if (set && subtype != VSPLUS) {
		/* insert the value of the variable */
		if (special) {
			varvalue(var, varflags & VSQUOTE, subtype, flag);
			if (subtype == VSLENGTH) {
				varlenb = expdest - stackblock() - startloc;
				varlen = varlenb;
				if (localeisutf8) {
					val = stackblock() + startloc;
					for (;val != expdest; val++)
						if ((*val & 0xC0) == 0x80)
							varlen--;
				}
				STADJUST(-varlenb, expdest);
			}
		} else {
			char const *syntax = (varflags & VSQUOTE) ? DQSYNTAX
								  : BASESYNTAX;

			if (subtype == VSLENGTH) {
				for (;*val; val++)
					if (!localeisutf8 ||
					    (*val & 0xC0) != 0x80)
						varlen++;
			}
			else {
				if (quotes)
					STPUTS_QUOTES(val, syntax, expdest);
				else
					STPUTS(val, expdest);

			}
		}
	}

	if (subtype == VSPLUS)
		set = ! set;

	easy = ((varflags & VSQUOTE) == 0 ||
		(*var == '@' && shellparam.nparam != 1));


	switch (subtype) {
	case VSLENGTH:
		expdest = cvtnum(varlen, expdest);
		goto record;

	case VSNORMAL:
		if (!easy)
			break;
record:
		recordregion(startloc, expdest - stackblock(),
		    varflags & VSQUOTE || (ifsset() && ifsval()[0] == '\0' &&
		    (*var == '@' || *var == '*')));
		break;

	case VSPLUS:
	case VSMINUS:
		if (!set) {
			argstr(p, flag | (flag & EXP_FULL ? EXP_SPLIT_LIT : 0) |
			    (varflags & VSQUOTE ? EXP_LIT_QUOTED : 0));
			break;
		}
		if (easy)
			goto record;
		break;

	case VSTRIMLEFT:
	case VSTRIMLEFTMAX:
	case VSTRIMRIGHT:
	case VSTRIMRIGHTMAX:
		if (!set)
			break;
		/*
		 * Terminate the string and start recording the pattern
		 * right after it
		 */
		STPUTC('\0', expdest);
		patloc = expdest - stackblock();
		if (subevalvar(p, NULL, patloc, subtype,
		    startloc, varflags, quotes) == 0) {
			int amount = (expdest - stackblock() - patloc) + 1;
			STADJUST(-amount, expdest);
		}
		/* Remove any recorded regions beyond start of variable */
		removerecordregions(startloc);
		goto record;

	case VSASSIGN:
	case VSQUESTION:
		if (!set) {
			if (subevalvar(p, var, 0, subtype, startloc, varflags,
			    quotes)) {
				varflags &= ~VSNUL;
				/*
				 * Remove any recorded regions beyond
				 * start of variable
				 */
				removerecordregions(startloc);
				goto again;
			}
			break;
		}
		if (easy)
			goto record;
		break;

	case VSERROR:
		c = p - var - 1;
		error("${%.*s%s}: Bad substitution", c, var,
		    (c > 0 && *p != CTLENDVAR) ? "..." : "");

	default:
		abort();
	}
	p[-1] = '=';	/* recover overwritten '=' */

	if (subtype != VSNORMAL) {	/* skip to end of alternative */
		int nesting = 1;
		for (;;) {
			if ((c = *p++) == CTLESC)
				p++;
			else if (c == CTLBACKQ || c == (CTLBACKQ|CTLQUOTE)) {
				if (set)
					argbackq = argbackq->next;
			} else if (c == CTLVAR) {
				if ((*p++ & VSTYPE) != VSNORMAL)
					nesting++;
			} else if (c == CTLENDVAR) {
				if (--nesting == 0)
					break;
			}
		}
	}
	return p;
}
Exemplo n.º 2
0
static const char *
evalvar(const char *p, int flag, struct worddest *dst)
{
	int subtype;
	int varflags;
	const char *var;
	const char *val;
	int patloc;
	int c;
	int set;
	int special;
	int startloc;
	int varlen;
	int varlenb;
	char buf[21];

	varflags = (unsigned char)*p++;
	subtype = varflags & VSTYPE;
	var = p;
	special = 0;
	if (! is_name(*p))
		special = 1;
	p = strchr(p, '=') + 1;
again: /* jump here after setting a variable with ${var=text} */
	if (varflags & VSLINENO) {
		set = 1;
		special = 1;
		val = NULL;
	} else if (special) {
		set = varisset(var, varflags & VSNUL);
		val = NULL;
	} else {
		val = bltinlookup(var, 1);
		if (val == NULL || ((varflags & VSNUL) && val[0] == '\0')) {
			val = NULL;
			set = 0;
		} else
			set = 1;
	}
	varlen = 0;
	startloc = expdest - stackblock();
	if (!set && uflag && *var != '@' && *var != '*') {
		switch (subtype) {
		case VSNORMAL:
		case VSTRIMLEFT:
		case VSTRIMLEFTMAX:
		case VSTRIMRIGHT:
		case VSTRIMRIGHTMAX:
		case VSLENGTH:
			error("%.*s: parameter not set", (int)(p - var - 1),
			    var);
		}
	}
	if (set && subtype != VSPLUS) {
		/* insert the value of the variable */
		if (special) {
			if (varflags & VSLINENO) {
				if (p - var > (ptrdiff_t)sizeof(buf))
					abort();
				memcpy(buf, var, p - var - 1);
				buf[p - var - 1] = '\0';
				strtodest(buf, flag, subtype,
				    varflags & VSQUOTE, dst);
			} else
				varvalue(var, varflags & VSQUOTE, subtype, flag,
				    dst);
			if (subtype == VSLENGTH) {
				varlenb = expdest - stackblock() - startloc;
				varlen = varlenb;
				if (localeisutf8) {
					val = stackblock() + startloc;
					for (;val != expdest; val++)
						if ((*val & 0xC0) == 0x80)
							varlen--;
				}
				STADJUST(-varlenb, expdest);
			}
		} else {
			if (subtype == VSLENGTH) {
				for (;*val; val++)
					if (!localeisutf8 ||
					    (*val & 0xC0) != 0x80)
						varlen++;
			}
			else
				strtodest(val, flag, subtype,
				    varflags & VSQUOTE, dst);
		}
	}

	if (subtype == VSPLUS)
		set = ! set;

	switch (subtype) {
	case VSLENGTH:
		cvtnum(varlen, buf);
		strtodest(buf, flag, VSNORMAL, varflags & VSQUOTE, dst);
		break;

	case VSNORMAL:
		break;

	case VSPLUS:
	case VSMINUS:
		if (!set) {
			argstr(p, flag | (flag & EXP_SPLIT ? EXP_SPLIT_LIT : 0) |
			    (varflags & VSQUOTE ? EXP_LIT_QUOTED : 0), dst);
			break;
		}
		break;

	case VSTRIMLEFT:
	case VSTRIMLEFTMAX:
	case VSTRIMRIGHT:
	case VSTRIMRIGHTMAX:
		if (!set)
			break;
		/*
		 * Terminate the string and start recording the pattern
		 * right after it
		 */
		STPUTC('\0', expdest);
		patloc = expdest - stackblock();
		subevalvar_trim(p, patloc, subtype, startloc);
		reprocess(startloc, flag, VSNORMAL, varflags & VSQUOTE, dst);
		if (flag & EXP_SPLIT && *var == '@' && varflags & VSQUOTE)
			dst->state = WORD_QUOTEMARK;
		break;

	case VSASSIGN:
	case VSQUESTION:
		if (!set) {
			if (subevalvar_misc(p, var, subtype, startloc,
			    varflags)) {
				varflags &= ~VSNUL;
				goto again;
			}
			break;
		}
		break;

	case VSERROR:
		c = p - var - 1;
		error("${%.*s%s}: Bad substitution", c, var,
		    (c > 0 && *p != CTLENDVAR) ? "..." : "");

	default:
		abort();
	}

	if (subtype != VSNORMAL) {	/* skip to end of alternative */
		int nesting = 1;
		for (;;) {
			if ((c = *p++) == CTLESC)
				p++;
			else if (c == CTLBACKQ || c == (CTLBACKQ|CTLQUOTE)) {
				if (set)
					argbackq = argbackq->next;
			} else if (c == CTLVAR) {
				if ((*p++ & VSTYPE) != VSNORMAL)
					nesting++;
			} else if (c == CTLENDVAR) {
				if (--nesting == 0)
					break;
			}
		}
	}
	return p;
}