From 6ddee9d1ef27e43546b28247b25f9017e6ede695 Mon Sep 17 00:00:00 2001 From: Cojocaru Alexandru Date: Sat, 4 May 2013 21:51:59 +0000 Subject: [PATCH] cut: keep benefits of bitarray even with `--output-delimiter' eol_range_start: removed, `n-' is no more treated specially complement_rp: used to complement `rp' when `--complement' is specified ADD_RANGE_PAIR: macro renamed to `add_range_pair' add_range_pair: function renamed from `ADD_RANGE_PAIR' set_fields: fix merging, `j' wasn't decremented as needed --- src/cut.c | 242 ++++++++++++++++++++++---------------------------------------- 1 file changed, 85 insertions(+), 157 deletions(-) diff --git a/src/cut.c b/src/cut.c index b347b30..ce5b742 100644 --- a/src/cut.c +++ b/src/cut.c @@ -80,21 +80,15 @@ static size_t n_rp_allocated; space if necessary. Update global variable N_RP. When allocating, update global variable N_RP_ALLOCATED. */ -#define ADD_RANGE_PAIR(rp, low, high) \ - do \ - { \ - if (low == 0 || high == 0) \ - FATAL_ERROR (_("fields and positions are numbered from 1")); \ - if (n_rp >= n_rp_allocated) \ - { \ - (rp) = X2NREALLOC (rp, &n_rp_allocated); \ - } \ - rp[n_rp].lo = (low); \ - rp[n_rp].hi = (high); \ - ++n_rp; \ - } \ - while (0) - +static void +add_range_pair (size_t lo, size_t hi) +{ + if (n_rp == n_rp_allocated) + rp = X2NREALLOC (rp, &n_rp_allocated); + rp[n_rp].lo = lo; + rp[n_rp].hi = hi; + ++n_rp; +} /* This buffer is used to support the semantics of the -s option (or lack of same) when the specified field list includes (does @@ -108,31 +102,6 @@ static char *field_1_buffer; /* The number of bytes allocated for FIELD_1_BUFFER. */ static size_t field_1_bufsize; -/* The largest field or byte index used as an endpoint of a closed - or degenerate range specification; this doesn't include the starting - index of right-open-ended ranges. For example, with either range spec - '2-5,9-', '2-3,5,9-' this variable would be set to 5. */ -static size_t max_range_endpoint; - -/* If nonzero, this is the index of the first field in a range that goes - to end of line. */ -static size_t eol_range_start; - -/* This is a bit vector. - In byte mode, which bytes to output. - In field mode, which DELIM-separated fields to output. - Both bytes and fields are numbered starting with 1, - so the zeroth bit of this array is unused. - A field or byte K has been selected if - (K <= MAX_RANGE_ENDPOINT && is_printable_field (K)) - || (EOL_RANGE_START > 0 && K >= EOL_RANGE_START). */ -static unsigned char *printable_field; - -/* The maximum size the printable_field array to allocate. - For ranges requiring more than this, we revert to the slightly - slower mechanism of inspecting the current range pair limits. */ -enum { PRINTABLE_ARRAY_MAX = 65536 }; - enum operating_mode { undefined_mode, @@ -151,7 +120,7 @@ static enum operating_mode operating_mode; with field mode. */ static bool suppress_non_delimited; -/* If nonzero, print all bytes, characters, or fields _except_ +/* If true, print all bytes, characters, or fields _except_ those that were specified. */ static bool complement; @@ -253,56 +222,6 @@ With no FILE, or when FILE is -, read standard input.\n\ exit (status); } -static inline void -mark_printable_field (size_t i) -{ - size_t n = i / CHAR_BIT; - printable_field[n] |= (1 << (i % CHAR_BIT)); -} - -static inline bool -is_printable_field (size_t i) -{ - size_t n = i / CHAR_BIT; - return (printable_field[n] >> (i % CHAR_BIT)) & 1; -} - -/* Return nonzero if the K'th field or byte is printable. - Note this is a "hot" function. Please profile when changing. */ - -static inline bool -print_kth (size_t k) -{ - bool k_selected = false; - - if (0 < eol_range_start && eol_range_start <= k) - k_selected = true; - else if (printable_field) /* faster path for smaller ranges. */ - { - if (k <= max_range_endpoint && is_printable_field (k)) - k_selected = true; - } - else if (current_rp->lo <= k && k <= current_rp->hi) - k_selected = true; - - return k_selected ^ complement; -} - -/* Return nonzero if K'th byte is the beginning of a range. */ - -static inline bool -is_range_start_index (size_t k) -{ - bool is_start = false; - - if (!complement) - is_start = (k == eol_range_start || k == current_rp->lo); - else - is_start = (k == (current_rp - 1)->hi + 1); - - return is_start; -} - /* Comparison function for qsort to order the list of struct range_pairs. */ static int @@ -313,22 +232,37 @@ compare_ranges (const void *a, const void *b) return a_start < b_start ? -1 : a_start > b_start; } -/* Increment *ITEM_IDX (i.e. a field or byte index), - and if required CURRENT_RP. */ - -static inline void -next_item (size_t *item_idx) +static void +complement_rp (void) { - (*item_idx)++; - /* avoid extra processing associated with current_rp unless needed. */ - if (!printable_field) - if ((*item_idx > current_rp->hi) && (current_rp < rp + n_rp - 1)) - current_rp++; -} + if (complement) + { + struct range_pair *c = rp; + size_t n = n_rp; + size_t i; + + rp = NULL; + n_rp = 0; + n_rp_allocated = 0; + + if (c[0].lo > 1) + add_range_pair (1, c[0].lo - 1); + for (i = 1; i < n; ++i) + { + if (c[i-1].hi + 1 == c[i].lo) + continue; + add_range_pair (c[i-1].hi + 1, c[i].lo - 1); + } + + if (c[n-1].hi < (size_t)-1) + add_range_pair (c[n-1].hi + 1, (size_t)-1); + + free (c); + } +} /* Given the list of field or byte range specifications FIELDSTR, - allocate and initialize the RP array. If there is a right-open-ended - range, set EOL_RANGE_START to its starting index. FIELDSTR should + allocate and initialize the RP array. FIELDSTR should be composed of one or more numbers or ranges of numbers, separated by blanks or commas. Incomplete ranges may be given: '-m' means '1-m'; 'n-' means 'n' through end of line. @@ -342,15 +276,14 @@ set_fields (const char *fieldstr) size_t value = 0; /* If nonzero, a number being accumulated. */ bool lhs_specified = false; bool rhs_specified = false; - bool dash_found = false; /* True if a '-' is found in this field. */ + bool dash_found = false; /* True if a `-' is found in this field. */ bool field_found = false; /* True if at least one field spec has been processed. */ size_t i; bool in_digits = false; - /* Collect and store in RP the range end points. - It also sets EOL_RANGE_START if appropriate. */ + /* Collect and store in RP the range end points. */ while (true) { @@ -382,22 +315,20 @@ set_fields (const char *fieldstr) FATAL_ERROR (_("invalid range with no endpoint: -")); /* A range. Possibilities: -n, m-n, n-. - In any case, 'initial' contains the start of the range. */ + In any case, `initial' contains the start of the range. */ if (!rhs_specified) { - /* 'n-'. From 'initial' to end of line. If we've already - seen an M- range, ignore subsequent N- unless N < M. */ - if (eol_range_start == 0 || initial < eol_range_start) - eol_range_start = initial; + /* `n-'. From `initial' to end of line. */ + add_range_pair (initial, (size_t)-1); field_found = true; } else { - /* 'm-n' or '-n' (1-n). */ + /* `m-n' or `-n' (1-n). */ if (value < initial) FATAL_ERROR (_("invalid decreasing range")); - ADD_RANGE_PAIR (rp, initial, value); + add_range_pair (initial, value); field_found = true; } value = 0; @@ -405,7 +336,9 @@ set_fields (const char *fieldstr) else { /* A simple field number, not a range. */ - ADD_RANGE_PAIR (rp, value, value); + if (value == 0) + FATAL_ERROR (_("fields and positions are numbered from 1")); + add_range_pair (value, value); value = 0; field_found = true; } @@ -455,71 +388,66 @@ set_fields (const char *fieldstr) FATAL_ERROR (_("invalid byte, character or field list")); } - max_range_endpoint = 0; - for (i = 0; i < n_rp; i++) - { - if (rp[i].hi > max_range_endpoint) - max_range_endpoint = rp[i].hi; - } - - /* For performance, allocate an array large enough so that it may be - indexed by the field numbers corresponding to all finite ranges - (i.e. '2-6' or '-4', but not '5-') in FIELDSTR. - Note this enhancement is not possible with very large ranges, - or when --output-delimiter is specified. */ - - if (!output_delimiter_specified - && max_range_endpoint - && max_range_endpoint / CHAR_BIT < PRINTABLE_ARRAY_MAX) - printable_field = xzalloc (max_range_endpoint / CHAR_BIT + 1); - qsort (rp, n_rp, sizeof (rp[0]), compare_ranges); - /* Omit finite ranges subsumed by a to-EOL range. */ - if (eol_range_start && n_rp) - { - i = n_rp; - while (i && eol_range_start <= rp[i - 1].hi) - { - eol_range_start = MIN (rp[i - 1].lo, eol_range_start); - --n_rp; - --i; - } - } - - /* Merge finite range pairs (e.g. `2-5,3-4' becomes `2-5'). - Also for small enough ranges, mark items as printable. */ + /* Merge range pairs (e.g. `2-5,3-4' becomes `2-5'). */ for (i = 0; i < n_rp; ++i) { - for (size_t j = i + 1; j < n_rp; ++j) + size_t j; + for (j = i + 1; j < n_rp; ++j) { if (rp[j].lo <= rp[i].hi) { rp[i].hi = MAX (rp[j].hi, rp[i].hi); memmove (rp + j, rp + j + 1, - (n_rp - j - 1) * sizeof (struct range_pair)); + (n_rp - j - 1) * sizeof (rp[0])); --n_rp; + --j; } else break; } - - if (printable_field) - { - for (size_t k = rp[i].lo; k <= rp[i].hi; k++) - mark_printable_field (k); - } } + complement_rp (); + /* After merging, reallocate RP so we release memory to the system. - Also add a sentinel at the end of RP, to avoid out of bounds access. */ + Also add a sentinel at the end of RP, to avoid out of bounds access + and for perfomance reasons. */ ++n_rp; rp = xrealloc (rp, n_rp * sizeof (struct range_pair)); - rp[n_rp - 1].lo = rp[n_rp - 1].hi = 0; + rp[n_rp - 1].lo = rp[n_rp - 1].hi = (size_t)-1; return field_found; } +/* Increment *ITEM_IDX (i.e. a field or byte index), + and if required CURRENT_RP. */ + +static inline void +next_item (size_t *item_idx) +{ + (*item_idx)++; + if ((*item_idx) > current_rp->hi) + current_rp++; +} + +/* Return nonzero if the K'th field or byte is printable. */ + +static inline bool +print_kth (size_t k) +{ + return current_rp->lo <= k; +} + +/* Return nonzero if K'th byte is the beginning of a range. */ + +static inline bool +is_range_start_index (size_t k) +{ + return k == current_rp->lo; +} + /* Read from stream STREAM, printing to standard output any selected bytes. */ static void -- 1.8.2.2