From f5e75663fef044cad02eef3eb7aef295312c1158 Mon Sep 17 00:00:00 2001 From: Laurent Bercot Date: Wed, 9 Oct 2019 15:07:23 +0000 Subject: Add path_canonicalize, prepare for 2.9.1.0 --- src/libstddjb/path_canonicalize.c | 69 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 69 insertions(+) create mode 100644 src/libstddjb/path_canonicalize.c (limited to 'src/libstddjb') diff --git a/src/libstddjb/path_canonicalize.c b/src/libstddjb/path_canonicalize.c new file mode 100644 index 0000000..c30f9f4 --- /dev/null +++ b/src/libstddjb/path_canonicalize.c @@ -0,0 +1,69 @@ +/* ISC license. */ + +#include +#include + +#include + +static unsigned char cclass (char c) +{ + switch (c) + { + case 0 : return 0 ; + case '/' : return 1 ; + case '.' : return 2 ; + default : return 3 ; + } +} + + /* out must be at least strlen(in) + 2 bytes */ + +size_t path_canonicalize (char *out, char const *in, int check) +{ + static unsigned char const table[4][4] = + { + { 0x04, 0x00, 0x12, 0x11 }, + { 0x04, 0x50, 0x11, 0x11 }, + { 0x24, 0x20, 0x13, 0x11 }, + { 0xa4, 0xa0, 0x11, 0x11 } + } ; + int isabsolute = in[0] == '/' ; + size_t j = 0 ; + unsigned int depth = 0 ; + unsigned char state = 0 ; + + if (isabsolute) *out++ = *in++ ; + while (state < 4) + { + char c = *in++ ; + unsigned char what = table[state][cclass(c)] ; + state = what & 0x07 ; + if (what & 0x80) + { + if (depth) + { + depth-- ; + j -= 3 ; + if (check) + { + struct stat st ; + out[j] = 0 ; + if (stat(out - isabsolute, &st) < 0) return 0 ; + if (!S_ISDIR(st.st_mode)) return (errno = ENOTDIR, 0) ; + } + } + else if (!isabsolute) + { + out[j++] = '/' ; + out[j++] = '.' ; + } + } + if (what & 0x40) depth++ ; + if (what & 0x20) while (j && out[j-1] != '/') j-- ; + if (what & 0x10) out[j++] = c ; + } + if (j && out[j-1] == '/') j-- ; + if (!j && !isabsolute) out[j++] = '.' ; + out[j] = 0 ; + return j ; +} -- cgit v1.2.3