diff options
| -rw-r--r-- | expand.c | 131 |
1 files changed, 87 insertions, 44 deletions
@@ -103,6 +103,30 @@ recursively_expand (v) return value; } + +/* Expand a simple reference to variable NAME, which LENGTH chars long. */ + +#ifdef __GNUC__ +__inline +#endif +static char * +reference_variable (o, name, length) + char *o; + char *name; + unsigned int length; +{ + register struct variable *v = lookup_variable (name, length); + + if (v != 0 && *v->value != '\0') + { + char *value = (v->recursive ? recursively_expand (v) : v->value); + o = variable_buffer_output (o, value, strlen (value)); + if (v->recursive) + free (value); + } + + return o; +} /* Scan LINE for variable references and expansion-function calls. Build in `variable_buffer' the result of expanding the references and calls. @@ -151,6 +175,7 @@ variable_expand (line) register char *beg = p + 1; char *op, *begp; char *end; + char *colon = 0; op = o; begp = p; @@ -167,7 +192,7 @@ variable_expand (line) p1 = index (beg, closeparen); if (p1 != 0) p1 = lindex (beg, p1, '$'); - if (p1 != 0) + if (p1 != 0 && lindex (beg, p1, ':') == 0) { /* BEG now points past the opening paren or brace. Count parens or braces until it is matched. */ @@ -178,22 +203,41 @@ variable_expand (line) ++count; else if (*p == closeparen && --count < 0) break; + else if (colon == 0 && count == 0 && *p == ':') + /* Record where we found a colon, which + indicates a substitution reference. + We want to expand the text before the + reference only. */ + colon = p; } /* If COUNT is >= 0, there were unmatched opening parens or braces, so we go to the simple case of a variable name such as `$($(a)'. */ if (count < 0) { - char *name = expand_argument (beg, p); - static char start[3] = { '$', }, end[2]; - start[1] = openparen; - end[0] = closeparen; - p1 = concat (start, name, end); - free (name); - name = allocated_variable_expand (p1); - o = variable_buffer_output (o, name, strlen (name)); - free (name); - break; + char *name = expand_argument (beg, colon == 0 ? p : colon); + unsigned int namelen = strlen (name); + if (colon == 0) + { + /* This is a simple reference to the expanded name. */ + o = reference_variable (o, name, namelen); + free (name); + break; + } + else + { + /* This is a substitution reference to the expanded + name. We replace the pending text with a copy + containing the expanded name in place of the + original name, and then fall through to + the normal substitution reference code below. */ + unsigned int restlen = strlen (colon) + 1; + beg = (char *) alloca (namelen + restlen); + bcopy (name, beg, namelen); + bcopy (colon, &beg[namelen], restlen); + /* Point COLON into the new copy. */ + colon = &beg[namelen]; + } } } @@ -201,17 +245,17 @@ variable_expand (line) it does not contain any variable references inside. There are several things it could be. */ - p = index (beg, ':'); - if (p != 0 && lindex (beg, p, closeparen) == 0) + if (colon == 0) + colon = index (beg, ':'); + if (colon != 0 && lindex (beg, colon, closeparen) == 0) { /* This is a substitution reference: $(FOO:A=B). */ int count; - char *subst_beg, *replace_beg; - unsigned int subst_len, replace_len; + char *subst_beg, *subst_end, *replace_beg, *replace_end; - v = lookup_variable (beg, p - beg); + v = lookup_variable (beg, colon - beg); - subst_beg = p + 1; + subst_beg = colon + 1; count = 0; for (p = subst_beg; *p != '\0'; ++p) { @@ -225,7 +269,7 @@ variable_expand (line) if (count > 0) /* There were unmatched opening parens. */ return initialize_variable_output (); - subst_len = p - subst_beg; + subst_end = p; replace_beg = p + 1; count = 0; @@ -240,27 +284,29 @@ variable_expand (line) /* There were unmatched opening parens. */ return initialize_variable_output (); end = p; - replace_len = p - replace_beg; + replace_end = p; + + p = expand_argument (subst_beg, subst_end); + p1 = expand_argument (replace_beg, replace_end); if (v != 0 && *v->value != '\0') { char *value = (v->recursive ? recursively_expand (v) : v->value); - if (lindex (subst_beg, subst_beg + subst_len, '%') != 0) - { - p = savestring (subst_beg, subst_len); - p1 = savestring (replace_beg, replace_len); - o = patsubst_expand (o, value, p, p1, - (char *) 0, (char *) 0); - free (p); - free (p1); - } + char *percent = find_percent (p); + if (percent != 0) + o = patsubst_expand (o, value, p, p1, + percent, (char *) 0); else - o = subst_expand (o, value, subst_beg, replace_beg, - subst_len, replace_len, 0, 1); + o = subst_expand (o, value, + p, p1, strlen (p), strlen (p1), + 0, 1); if (v->recursive) free (value); } + + free (p); + free (p1); } /* No, this must be an ordinary variable reference. */ @@ -270,16 +316,7 @@ variable_expand (line) end = index (beg, closeparen); if (end == 0) return initialize_variable_output (); - v = lookup_variable (beg, end - beg); - - if (v != 0 && *v->value != '\0') - { - char *value = (v->recursive ? recursively_expand (v) - : v->value); - o = variable_buffer_output (o, value, strlen (value)); - if (v->recursive) - free (value); - } + o = reference_variable (o, beg, end - beg); } /* Advance p past the variable reference to resume scan. */ @@ -333,12 +370,18 @@ char * expand_argument (str, end) char *str, *end; { - char *tmp = savestring (str, end - str); - char *value = allocated_variable_expand (tmp); + char *tmp; - free (tmp); + if (*end == '\0') + tmp = str; + else + { + tmp = (char *) alloca (end - str + 1); + bcopy (str, tmp, end - str); + tmp[end - str] = '\0'; + } - return value; + return allocated_variable_expand (tmp); } /* Expand LINE for FILE. Error messages refer to the file and line where |