diff options
Diffstat (limited to 'shell/math.c')
| -rw-r--r-- | shell/math.c | 84 |
1 files changed, 48 insertions, 36 deletions
diff --git a/shell/math.c b/shell/math.c index ac75863..fbf5c58 100644 --- a/shell/math.c +++ b/shell/math.c @@ -531,29 +531,11 @@ static const char op_tokens[] ALIGN1 = { #define END_POINTER (&op_tokens[sizeof(op_tokens)-1]) #if ENABLE_FEATURE_SH_MATH_BASE -static arith_t strto_arith_t(const char *nptr, char **endptr) +static arith_t parse_with_base(const char *nptr, char **endptr, unsigned base) { - unsigned base; - arith_t n; - -# if ENABLE_FEATURE_SH_MATH_64 - n = strtoull(nptr, endptr, 0); -# else - n = strtoul(nptr, endptr, 0); -# endif - if (**endptr != '#' - || (*nptr < '1' || *nptr > '9') - || (n < 2 || n > 64) - ) { - return n; - } + arith_t n = 0; + const char *start = nptr; - /* It's "N#nnnn" or "NN#nnnn" syntax, NN can't start with 0, - * NN is in 2..64 range. - */ - base = (unsigned)n; - n = 0; - nptr = *endptr + 1; for (;;) { unsigned digit = (unsigned)*nptr - '0'; if (digit >= 10 /* not 0..9 */ @@ -582,15 +564,52 @@ static arith_t strto_arith_t(const char *nptr, char **endptr) n = n * base + digit; nptr++; } - /* Note: we do not set errno on bad chars, we just set a pointer - * to the first invalid char. For example, this allows - * "N#" (empty "nnnn" part): 64#+1 is a valid expression, - * it means 64# + 1, whereas 64#~... is not, since ~ is not a valid - * operator. - */ *endptr = (char*)nptr; + /* "64#" and "64#+1" used to be valid expressions, but bash 5.2.15 + * no longer allow such, detect this: + */ +// NB: bash allows $((0x)), this is probably a bug... + if (nptr == start) + *endptr = NULL; /* there weren't any digits, bad */ return n; } + +static arith_t strto_arith_t(const char *nptr, char **endptr) +{ +/* NB: we do not use strtoull here to be bash-compatible: + * $((99999999999999999999)) is 7766279631452241919 + * (the 64-bit truncated value). + */ + unsigned base; + + /* nptr[0] is '0'..'9' here */ + + base = nptr[0] - '0'; + if (base == 0) { /* nptr[0] is '0' */ + base = 8; + if ((nptr[1] | 0x20) == 'x') { + base = 16; + nptr += 2; + } +// NB: bash allows $((0x)), this is probably a bug... + return parse_with_base(nptr, endptr, base); + } + + if (nptr[1] == '#') { + if (base > 1) + return parse_with_base(nptr + 2, endptr, base); + /* else: bash says "invalid arithmetic base" */ + } + + if (isdigit(nptr[1]) && nptr[2] == '#') { + base = 10 * base + (nptr[1] - '0'); + if (base >= 2 && base <= 64) + return parse_with_base(nptr + 3, endptr, base); + /* else: bash says "invalid arithmetic base" */ + } + + return parse_with_base(nptr, endptr, 10); +} #else /* !ENABLE_FEATURE_SH_MATH_BASE */ # if ENABLE_FEATURE_SH_MATH_64 # define strto_arith_t(nptr, endptr) strtoull(nptr, endptr, 0) @@ -702,7 +721,6 @@ evaluate_string(arith_state_t *math_state, const char *expr) dbg("[%d] var:IGNORED", (int)(numstackptr - numstack)); expr = p; numstackptr->var_name = NULL; - push_num0: numstackptr->val = 0; } push_num: @@ -715,11 +733,12 @@ evaluate_string(arith_state_t *math_state, const char *expr) /* Number */ char *end; numstackptr->var_name = NULL; - errno = 0; /* code is smaller compared to using &expr here: */ numstackptr->val = strto_arith_t(expr, &end); expr = end; dbg("[%d] val:%lld", (int)(numstackptr - numstack), numstackptr->val); + if (!expr) /* example: $((10#)) */ + goto syntax_err; /* A number can't be followed by another number, or a variable name. * We'd catch this later anyway, but this would require numstack[] * to be ~twice as deep to handle strings where _every_ char is @@ -728,13 +747,6 @@ evaluate_string(arith_state_t *math_state, const char *expr) */ if (isalnum(*expr) || *expr == '_') goto syntax_err; - if (errno) { -// TODO: bash 5.2.15 does not catch ERANGE (some older version did?). -// $((99999999999999999999)) is 7766279631452241919 (the 64-bit truncated value). -// Our BASE# code does this as well: try $((10#99999999999999999999)), -// but the "ordinary" code path with strtoull() does not do this. - goto push_num0; /* bash compat */ - } goto push_num; } |