From aeb379edee99467978b2b8451805884c005c46d5 Mon Sep 17 00:00:00 2001 From: Martin Mares Date: Sun, 22 Jun 2014 16:29:03 +0200 Subject: [PATCH] Docs: Polish table printer documentation --- ucw/doc/table.txt | 21 ++++++------- ucw/table.h | 80 +++++++++++++++++++++++++++-------------------- 2 files changed, 56 insertions(+), 45 deletions(-) diff --git a/ucw/doc/table.txt b/ucw/doc/table.txt index 22e6119d..b52bc688 100644 --- a/ucw/doc/table.txt +++ b/ucw/doc/table.txt @@ -24,7 +24,6 @@ Let us construct a simple table of music recordings: First, we define an enum with column indices (the values are automatically numbered starting from 0): - // Definition of columns enum table_columns { TBL_REC_ID, TBL_REC_ALBUM_NAME, @@ -33,9 +32,9 @@ numbered starting from 0): }; Then we create a structure with the definition of our table. -The table columns are defined using the `TBL_COL_xxx` and `TBL_COL_xxx_FMT` +The table columns are defined using the `TBL_COL_`'type' and `TBL_COL_`'type'`_FMT` macros. Each macro gets the name of the column and its default width -in character. The `_FMT` version has an additional argument: the format +in characters. The `_FMT` version adds an explicit format string for `printf` used for this column. Moreover, various flags can be OR-ed to the width of the column, for example `CELL_ALIGN_LEFT` prescribes that the cell should be aligned to the left. @@ -50,19 +49,19 @@ that the cell should be aligned to the left. } }; -Before you use the table definition, you need to initialize it: +Each table definition has to be initialized before use by @table_init(): table_init(&recording_table); -With a single definition, you can print multiple tables. At the start -of each table, you should obtain a <> where the output -should be sent, store it in the table structure and call table_start(): +Once it is initialized, we can use it for printing multiple tables. +At the start of each table, we should obtain a <> where the output +should be sent, store it in the table structure and call @table_start(): struct fastbuf *out = bfdopen_shared(1, 4096); table_start(&recording_table, out); -Then you can fill the rows one after another. Each row is ended by -table_end_row(): +Then we can fill the rows one after another. Each row is ended by +@table_end_row(): table_col_uint(&recording_table, TBL_REC_ID, 0); table_col_str(&recording_table, TBL_REC_ALBUM_NAME, "The Wall"); @@ -76,12 +75,12 @@ table_end_row(): table_col_uint(&recording_table, TBL_REC_YEAR, 1972); table_end_row(&recording_table); -Finally, you should close the table by calling table_end(): +Finally, we should close the table by calling @table_end(): table_end(&recording_table); At this moment, the table structure is ready to be used again. When -you do not need it any longer, you can dispose of it by table_cleanup(): +you do not need it any longer, you can dispose of it by @table_cleanup(): table_cleanup(&recording_table); diff --git a/ucw/table.h b/ucw/table.h index 0f2c8b13..6bec5652 100644 --- a/ucw/table.h +++ b/ucw/table.h @@ -56,7 +56,7 @@ * ----------------- ***/ -/** Types of columns. These are seldom used explicitly, a column definition macro is used instead. **/ +/** Types of columns. These are seldom used explicitly, using a column definition macro is preferred. **/ enum column_type { COL_TYPE_STR, // String COL_TYPE_INT, // int @@ -71,8 +71,8 @@ enum column_type { COL_TYPE_LAST }; -/** Column flag (to be OR-ed to column's width) **/ -#define CELL_ALIGN_LEFT (1U << 31) // Justify cell contents to the left +/** Justify cell contents to the left. **/ +#define CELL_ALIGN_LEFT (1U << 31) // CELL_FLAG_MASK has 1's in bits used for column flags, // CELL_WIDTH_MASK has 1's in bits used for column width. @@ -81,7 +81,7 @@ enum column_type { /** * Definition of a single table column. - * Usually, this is generated using the `TABLE_COL_xxx` macros. + * Usually, this is generated using the `TABLE_COL_`'type' macros. * Fields marked with `[*]` are user-accessible. **/ struct table_column { @@ -128,8 +128,8 @@ struct table { * See the examples above for more details. * * * `TBL_COLUMNS` indicates the start of definition of columns - * * `TBL_COL_xxx(name, width)` defines a column of type `xxx` - * * `TBL_COL_xxx_FMT(name, width, fmt)` defines a column with a custom format string + * * `TBL_COL_`'type'`(name, width)` defines a column of a given type + * * `TBL_COL_`'type'`_FMT(name, width, fmt)` defines a column with a custom format string * * `TBL_COL_END` ends the column definitions * * `TBL_COL_ORDER` specifies custom ordering of columns in the output * * `TBL_COL_DELIMITER` and `TBL_APPEND_DELIMITER` override default delimiters @@ -173,8 +173,8 @@ struct table { #define TBL_OUTPUT_MACHINE_READABLE .formatter = &table_fmt_machine_readable /** - * @table_init serves for initialization of the table. The structure should - * already contain the definitions of columns. + * Initialize a table definition. The structure should already contain + * the definitions of columns. **/ void table_init(struct table *tbl); @@ -183,15 +183,15 @@ void table_cleanup(struct table *tbl); /** * Start printing of a table. This is a prerequisite to setting of column values. - * After table_start() is called, it is no longer possible to change parameters - * of the table by `table_set_xxx` nor by direct access to the table structure. + * After @table_start() is called, it is no longer possible to change parameters + * of the table by `table_set_`'something' nor by direct access to the table structure. **/ void table_start(struct table *tbl, struct fastbuf *out); /** * This function must be called after all the rows of the current table are printed, - * making the table structure ready for the next table. You can call `table_set_*` - * between table_end() and table_start(). + * making the table structure ready for the next table. You can call `table_set_`'something' + * between @table_end() and @table_start(). **/ void table_end(struct table *tbl); @@ -253,7 +253,7 @@ void table_append_bool(struct table *tbl, int val); void table_col_printf(struct table *tbl, int col, const char *fmt, ...) FORMAT_CHECK(printf, 3, 4); /** - * Appends a string formatted by sprintf() to the most recently filled cell. + * Append a string formatted by sprintf() to the most recently filled cell. * This function can work with columns of an arbitrary type. **/ void table_append_printf(struct table *tbl, const char *fmt, ...) FORMAT_CHECK(printf, 2, 3); @@ -261,13 +261,13 @@ void table_append_printf(struct table *tbl, const char *fmt, ...) FORMAT_CHECK(p /** * Alternatively, a string cell can be constructed as a stream. * This function creates a fastbuf stream connected to the contents - * of the particular cell. Before you close the stream by table_col_fbend(), + * of the particular cell. Before you close the stream by @table_col_fbend(), * no other operations with cells are allowed. **/ struct fastbuf *table_col_fbstart(struct table *tbl, int col); /** - * Closes the stream that is used for printing of the current column. + * Close the stream that is used for printing of the current column. **/ void table_col_fbend(struct table *tbl); @@ -294,8 +294,8 @@ int table_get_col_idx(struct table *tbl, const char *col_name); const char *table_get_col_list(struct table *tbl); /** - * Sets the order in which the columns are printed. The @col_order parameter is used until table_end() or - * table_cleanup() is called. The table stores only the pointer and the memory pointed to by @col_order is + * Sets the order in which the columns are printed. The @col_order parameter is used until @table_end() or + * @table_cleanup() is called. The table stores only the pointer and the memory pointed to by @col_order is * allocated and deallocated by the caller. **/ void table_set_col_order(struct table *tbl, int *col_order, int col_order_size); @@ -308,7 +308,7 @@ void table_set_col_order(struct table *tbl, int *col_order, int col_order_size); const char *table_set_col_order_by_name(struct table *tbl, const char *col_order); /** - * Sets table formatter for @tbl. See below for the list of formatters. + * Sets table formatter. See below for the list of formatters. **/ void table_set_formatter(struct table *tbl, struct table_formatter *fmt); @@ -317,19 +317,19 @@ void table_set_formatter(struct table *tbl, struct table_formatter *fmt); * the following keys are defined (other keys can be accepted by formatters): * * [options="header"] - * |======================= - * | key | value | meaning - * | `header` | 0 or 1 | set whether a table header should be printed - * | `noheader` | 'none' | equivalent to `header`=0 - * | `cols` | column list | set order of columns (accepts a comma-separated list of column names) - * | `fmt` | formatter | set table formatter (`human`, `machine`, `block`) - * | `col-delim`| string | set column delimiter - * |======================== + * |=================================================================================================== + * | key | value | meaning + * | `header` | 0 or 1 | set whether a table header should be printed + * | `noheader` | 'none' | equivalent to `header`=0 + * | `cols` | comma-separated column list | set order of columns + * | `fmt` | `human`/`machine`/`block` | set table formatter to one of the built-in formatters + * | `col-delim`| string | set column delimiter + * |=================================================================================================== **/ const char *table_set_option_value(struct table *tbl, const char *key, const char *value); /** - * Sets a table option given as 'key'`:`'value' or `key` (with no value). + * Sets a table option given as 'key'`:`'value' or 'key' (with no value). **/ const char *table_set_option(struct table *tbl, const char *opt); @@ -343,10 +343,19 @@ const char *table_set_gary_options(struct table *tbl, char **gary_table_opts); * Formatters * ---------- * - * Each formatter defines several call-back functions, which are called - * by the table printer at specific points. The formatter can keep its internal - * state in the `data` field of `struct table` and allocate temporary data - * from the table's memory pool. + * Transformation of abstract cell data to the characters in the output stream + * is under control of a formatter (which serves as a back-end of the table printer). + * There are several built-in formatters, but you can define your own. + * + * A formatter is described by a structure, which contains pointers to several + * call-back functions, which are called by the table printer at specific occasions. + + * The formatter can keep its internal state in the `data` field of `struct table` + * and allocate temporary data from the table's memory pool. Memory allocated in + * the `row_output` call-back is freed before the next row begins. Memory allocated + * between the beginning of `table_start` and the end of `table_end` is freed after + * `table_end`. Memory allocated by `process_option` when no table is started + * is kept until @table_cleanup(). ***/ /** Definition of a formatter back-end. **/ @@ -358,13 +367,16 @@ struct table_formatter { // [*] Process table option and possibly return an error message (optional) }; -/** Standard formatter for human-readable output **/ +/** Standard formatter for human-readable output. **/ extern struct table_formatter table_fmt_human_readable; -/** Standard formatter for machine-readable output (tab-separated values) **/ +/** Standard formatter for machine-readable output (tab-separated values). **/ extern struct table_formatter table_fmt_machine_readable; -/** Standard formatter for block output (one cell per line) **/ +/** + * Standard formatter for block output. Each cell is output on its own line + * of the form `column_name: value`. Rows are separated by blank lines. + **/ extern struct table_formatter table_fmt_blockline; #endif -- 2.39.5