Remove unnecessary string copies #38
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eliottness
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Julio-Guerra
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cgo_ref_pool.go
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| goArray[len(str)] = 0 // Null termination byte for C strings | ||
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| return sliceToUintptr(goArray) | ||
| nullTerminated := str + "\x00" |
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This can lead to a copy whereas libddwaf can manage non-null terminated strings via ddwaf_object_stringl().
So I suggest we avoid this concatenation, by for example removing the existence of AllocCString (which has an unclear name with the 0-copy approach) and revisit this API to make it possible to avoid the concatenation here 🙏
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Today, AllocCString is not used for string WAF objects, it is only used to allocated strings for the obfuscator config. AllocWafString is used for all cases concerning the WAF objects, which indeed does not use null-terminated strings
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Documented the function
Signed-off-by: Eliott Bouhana <[email protected]>
Signed-off-by: Eliott Bouhana <[email protected]>
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Signed-off-by: Eliott Bouhana <[email protected]>
Hellzy
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Nov 6, 2023
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Since we upgraded the WAF to a version higher than 1.11, the input passed in are all read-only on the WAF side. Since this is the case we can remove unnecessary copies on our side