diff options
| -rw-r--r-- | include/PropSet.h | 2 | ||||
| -rw-r--r-- | src/PropSet.cxx | 92 |
2 files changed, 64 insertions, 30 deletions
diff --git a/include/PropSet.h b/include/PropSet.h index afd076c28..69f4c4b78 100644 --- a/include/PropSet.h +++ b/include/PropSet.h @@ -50,7 +50,7 @@ public: void SetMultiple(const char *s); SString Get(const char *key); SString GetExpanded(const char *key); - SString Expand(const char *withVars, int maxExpands=100, const char *blankVar=NULL); + SString Expand(const char *withVars, int maxExpands=100); int GetInt(const char *key, int defaultValue=0); SString GetWild(const char *keybase, const char *filename); SString GetNewExpand(const char *keybase, const char *filename=""); diff --git a/src/PropSet.cxx b/src/PropSet.cxx index b2265c597..3711c03c8 100644 --- a/src/PropSet.cxx +++ b/src/PropSet.cxx @@ -449,39 +449,71 @@ bool PropSet::IncludesVar(const char *value, const char *key) { return false; } -SString PropSet::GetExpanded(const char *key) { - SString val = Get(key); - return Expand(val.c_str(), 100, key); -} -SString PropSet::Expand(const char *withVars, int maxExpands, const char *blankVar) { - char *base = StringDup(withVars); - char *cpvar = strstr(base, "$("); - while (cpvar && (maxExpands > 0)) { - char *cpendvar = strchr(cpvar, ')'); - if (!cpendvar) +// There is some inconsistency between GetExpanded("foo") and Expand("$(foo)"). +// A solution is to keep a stack of variables that have been expanded, so that +// recursive expansions can be skipped. For now I'll just use the C++ stack +// for that, through a recursive function and a simple chain of pointers. + +struct VarChain { + VarChain(const char*var_=NULL, const VarChain *link_=NULL): var(var_), link(link_) {} + + bool contains(const char *testVar) const { + return (var && (0 == strcmp(var, testVar))) + || (link && link->contains(testVar)); + } + + const char *var; + const VarChain *link; +}; + +static int ExpandAllInPlace(PropSet &props, SString &withVars, int maxExpands, const VarChain &blankVars = VarChain()) { + int varStart = withVars.search("$("); + while ((varStart >= 0) && (maxExpands > 0)) { + int varEnd = withVars.search(")", varStart+2); + if (varEnd < 0) { break; - int lenvar = cpendvar - cpvar - 2; // Subtract the $() - char *var = StringDup(cpvar + 2, lenvar); - SString val = Get(var); - if (blankVar && (0 == strcmp(var, blankVar))) + } + + // For consistency, when we see '$(ab$(cde))', expand the inner variable first, + // regardless whether there is actually a degenerate variable named 'ab$(cde'. + int innerVarStart = withVars.search("$(", varStart+2); + while ((innerVarStart > varStart) && (innerVarStart < varEnd)) { + varStart = innerVarStart; + innerVarStart = withVars.search("$(", varStart+2); + } + + SString var(withVars.c_str(), varStart + 2, varEnd); + SString val = props.Get(var.c_str()); + + if (blankVars.contains(var.c_str())) { val.clear(); // treat blankVar as an empty string (e.g. to block self-reference) - if (IncludesVar(val.c_str(), var)) - break; - size_t newlenbase = strlen(base) + val.length() - lenvar; - char *newbase = new char[newlenbase]; - strncpy(newbase, base, cpvar - base); - strcpy(newbase + (cpvar - base), val.c_str()); - strcpy(newbase + (cpvar - base) + val.length(), cpendvar + 1); - delete []var; - delete []base; - base = newbase; - cpvar = strstr(base, "$("); - maxExpands--; + } + + if (--maxExpands >= 0) { + maxExpands = ExpandAllInPlace(props, val, maxExpands, VarChain(var.c_str(), &blankVars)); + } + + withVars.remove(varStart, varEnd-varStart+1); + withVars.insert(varStart, val.c_str(), val.length()); + + varStart = withVars.search("$("); } - SString sret = base; - delete []base; - return sret; + + return maxExpands; +} + + +SString PropSet::GetExpanded(const char *key) { + SString val = Get(key); + ExpandAllInPlace(*this, val, 100, VarChain(key)); + return val; +} + +SString PropSet::Expand(const char *withVars, int maxExpands) { + SString val = withVars; + ExpandAllInPlace(*this, val, maxExpands); + return val; } int PropSet::GetInt(const char *key, int defaultValue) { @@ -576,6 +608,8 @@ SString PropSet::GetWild(const char *keybase, const char *filename) { } } + + // GetNewExpand does not use Expand as it has to use GetWild with the filename for each // variable reference found. SString PropSet::GetNewExpand(const char *keybase, const char *filename) { |