fixes integer overflow in ucx_buffer_extract

fixes major bug in construction of KMP prefix table for strstr()

further performance tweaks to sstrstr() function

improves sstrstr function by using KMP string search algorithm

reduces amount of realloc calls in sstrsplit

adds an optimization for one-byte delimiters to sstrsplit (will take effect after planned reimplementation of sstrstr)

reimplementation of sstrsplit

adds new test case for sstrsplit: string ends with delimiter but empty string exceeds list bound

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mercurial