Ruby: Model the posix-spawn gem #8737
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#8635 has some more complex logic for identifying which arguments are passed to the spawned process - possibly we should try to share some of that to get the same benefits here. |
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| exists(API::Node spawn | spawn = API::getTopLevelMember("POSIX").getMember("Spawn") | | ||
| this = | ||
| posixSpawnModule() | ||
| .getAMethodCall(["spawn", "fspawn", "popen4", "pspawn", "system", "_pspawn", "`"]) | ||
| ) |
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You don't need the spawn variable:
| exists(API::Node spawn | spawn = API::getTopLevelMember("POSIX").getMember("Spawn") | | |
| this = | |
| posixSpawnModule() | |
| .getAMethodCall(["spawn", "fspawn", "popen4", "pspawn", "system", "_pspawn", "`"]) | |
| ) | |
| this = | |
| posixSpawnModule() | |
| .getAMethodCall(["spawn", "fspawn", "popen4", "pspawn", "system", "_pspawn", "`"]) | |
| ) |
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Ah yeah, remnant of some lazy refactoring on my part...
| exists(int n, int m, DataFlow::Node otherArg | | ||
| this.argument(arg, n) and | ||
| this.argument(otherArg, m) and |
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Could be simplified to the following, witihout loss of meaning
| exists(int n, int m, DataFlow::Node otherArg | | |
| this.argument(arg, n) and | |
| this.argument(otherArg, m) and | |
| exists(DataFlow::Node otherArg | | |
| this.argument(arg, _) and | |
| this.argument(otherArg, _) and |
And you probably want to add and not arg = otherArg.
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I also missed a not before the exists! Very sloppy. Should all be fixed now 🤞
| ) | ||
| } | ||
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| private predicate argument(DataFlow::Node arg, int n) { |
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And if you take my suggestion above, then it could be simplified more by removing this n param.
This gem exists primarily to provide methods that spawn subprocesses. We model these as SystemCommandExecutions.
This gem exists primarily to provide methods that spawn subprocesses. We
model these as
SystemCommandExecutions.