From 87e07ea9439cb4113f8425390f4a0f20861b5447 Mon Sep 17 00:00:00 2001 From: Damien George Date: Tue, 2 Feb 2016 15:51:57 +0000 Subject: [PATCH] py/objstr: For str.format, don't allocate on the heap for field name. --- py/objstr.c | 46 +++++++++++++++++++++++----------------------- 1 file changed, 23 insertions(+), 23 deletions(-) diff --git a/py/objstr.c b/py/objstr.c index c0f8c23b94..ed850baa7b 100644 --- a/py/objstr.c +++ b/py/objstr.c @@ -803,17 +803,16 @@ STATIC mp_obj_t str_rstrip(size_t n_args, const mp_obj_t *args) { // Takes an int arg, but only parses unsigned numbers, and only changes // *num if at least one digit was parsed. -STATIC int str_to_int(const char *str, int *num) { - const char *s = str; - if ('0' <= *s && *s <= '9') { +STATIC const char *str_to_int(const char *str, const char *top, int *num) { + if (str < top && '0' <= *str && *str <= '9') { *num = 0; do { - *num = *num * 10 + (*s - '0'); - s++; + *num = *num * 10 + (*str - '0'); + str++; } - while ('0' <= *s && *s <= '9'); + while (str < top && '0' <= *str && *str <= '9'); } - return s - str; + return str; } STATIC bool isalignment(char ch) { @@ -881,15 +880,17 @@ vstr_t mp_obj_str_format_helper(const char *str, const char *top, int *arg_i, mp // replacement_field ::= "{" [field_name] ["!" conversion] [":" format_spec] "}" - vstr_t *field_name = NULL; + const char *field_name = NULL; + const char *field_name_top = NULL; char conversion = '\0'; const char *format_spec = NULL; if (str < top && *str != '}' && *str != '!' && *str != ':') { - field_name = vstr_new(); + field_name = (const char *)str; while (str < top && *str != '}' && *str != '!' && *str != ':') { - vstr_add_byte(field_name, *str++); + ++str; } + field_name_top = (const char *)str; } // conversion ::= "r" | "s" @@ -958,9 +959,7 @@ vstr_t mp_obj_str_format_helper(const char *str, const char *top, int *arg_i, mp if (field_name) { int index = 0; - const char *field = vstr_null_terminated_str(field_name); - const char *lookup = NULL; - if (MP_LIKELY(unichar_isdigit(*field))) { + if (MP_LIKELY(unichar_isdigit(*field_name))) { if (*arg_i > 0) { if (MICROPY_ERROR_REPORTING == MICROPY_ERROR_REPORTING_TERSE) { terse_str_format_value_error(); @@ -969,26 +968,26 @@ vstr_t mp_obj_str_format_helper(const char *str, const char *top, int *arg_i, mp "can't switch from automatic field numbering to manual field specification")); } } - lookup = str_to_int(field, &index) + field; + field_name = str_to_int(field_name, field_name_top, &index); if ((uint)index >= n_args - 1) { nlr_raise(mp_obj_new_exception_msg(&mp_type_IndexError, "tuple index out of range")); } arg = args[index + 1]; *arg_i = -1; } else { - for (lookup = field; *lookup && *lookup != '.' && *lookup != '['; lookup++); - mp_obj_t field_q = mp_obj_new_str(field, lookup - field, true/*?*/); + const char *lookup; + for (lookup = field_name; lookup < field_name_top && *lookup != '.' && *lookup != '['; lookup++); + mp_obj_t field_q = mp_obj_new_str(field_name, lookup - field_name, true/*?*/); + field_name = lookup; mp_map_elem_t *key_elem = mp_map_lookup(kwargs, field_q, MP_MAP_LOOKUP); if (key_elem == NULL) { nlr_raise(mp_obj_new_exception_arg1(&mp_type_KeyError, field_q)); } arg = key_elem->value; } - if (*lookup) { + if (field_name < field_name_top) { mp_not_implemented("attributes not supported yet"); } - vstr_free(field_name); - field_name = NULL; } else { if (*arg_i < 0) { if (MICROPY_ERROR_REPORTING == MICROPY_ERROR_REPORTING_TERSE) { @@ -1045,6 +1044,7 @@ vstr_t mp_obj_str_format_helper(const char *str, const char *top, int *arg_i, mp MP_STACK_CHECK(); vstr_t format_spec_vstr = mp_obj_str_format_helper(format_spec, str, arg_i, n_args, args, kwargs); const char *s = vstr_null_terminated_str(&format_spec_vstr); + const char *stop = s + format_spec_vstr.len; if (isalignment(*s)) { align = *s++; } else if (*s && isalignment(s[1])) { @@ -1071,14 +1071,14 @@ vstr_t mp_obj_str_format_helper(const char *str, const char *top, int *arg_i, mp fill = '0'; } } - s += str_to_int(s, &width); + s = str_to_int(s, stop, &width); if (*s == ',') { flags |= PF_FLAG_SHOW_COMMA; s++; } if (*s == '.') { s++; - s += str_to_int(s, &precision); + s = str_to_int(s, stop, &precision); } if (istype(*s)) { type = *s++; @@ -1374,7 +1374,7 @@ STATIC mp_obj_t str_modulo_format(mp_obj_t pattern, mp_uint_t n_args, const mp_o width = mp_obj_get_int(args[arg_i++]); str++; } else { - str += str_to_int((const char*)str, &width); + str = (const byte*)str_to_int((const char*)str, (const char*)top, &width); } } int prec = -1; @@ -1388,7 +1388,7 @@ STATIC mp_obj_t str_modulo_format(mp_obj_t pattern, mp_uint_t n_args, const mp_o str++; } else { prec = 0; - str += str_to_int((const char*)str, &prec); + str = (const byte*)str_to_int((const char*)str, (const char*)top, &prec); } } }