For commands with with too few arguments, clear out args if it's an Array instead of replacing it with null in EvaluatorPreprocessor_read (issue 7804)

For `PartialEvaluator_getTextContent`, the same `args` Array should be re-used for every `EvaluatorPreprocessor_read` call. Hence we want to ensure that it's not accidentally replaced with `null` in `EvaluatorPreprocessor_read`, since otherwise corrupt PDF files (with too few arguments for certain commands) will cause errors in `PartialEvaluator_getTextContent`.

Perhaps a micro-optimization, but this patch also changes two `!args` comparisons to `args === null`, since that should be a tiny bit more efficient.
This commit is contained in:
Jonas Jenwald 2016-11-15 13:09:41 +01:00
parent 7f6a607ea5
commit a930f9af15

View File

@ -2850,7 +2850,7 @@ var EvaluatorPreprocessor = (function EvaluatorPreprocessorClosure() {
argsLength--;
}
while (argsLength < numArgs && nonProcessedArgs.length !== 0) {
if (!args) {
if (args === null) {
args = [];
}
args.unshift(nonProcessedArgs.pop());
@ -2859,17 +2859,18 @@ var EvaluatorPreprocessor = (function EvaluatorPreprocessorClosure() {
}
if (argsLength < numArgs) {
// If we receive too few args, it's not possible to possible
// to execute the command, so skip the command
info('Command ' + fn + ': because expected ' +
numArgs + ' args, but received ' + argsLength +
' args; skipping');
args = null;
// If we receive too few arguments, it's not possible to execute
// the command, hence we skip the command.
warn('Skipping command ' + fn + ': expected ' + numArgs +
' args, but received ' + argsLength + ' args.');
if (args !== null) {
args.length = 0;
}
continue;
}
} else if (argsLength > numArgs) {
info('Command ' + fn + ': expected [0,' + numArgs +
'] args, but received ' + argsLength + ' args');
'] args, but received ' + argsLength + ' args.');
}
// TODO figure out how to type-check vararg functions
@ -2884,7 +2885,7 @@ var EvaluatorPreprocessor = (function EvaluatorPreprocessorClosure() {
}
// argument
if (obj !== null) {
if (!args) {
if (args === null) {
args = [];
}
args.push(obj);