Save work on documentation updates.

This commit is contained in:
Michael R Sweet 2024-03-19 13:18:43 -04:00
parent 73c05c8b23
commit b438d21b9b
No known key found for this signature in database
GPG Key ID: BE67C75EC81F3244
4 changed files with 152 additions and 206 deletions

View File

@ -30,6 +30,8 @@ Mini-XML provides the following functionality:
"leaf" nodes.
- Functions for creating and managing trees of data.
- "Find" and "walk" functions for easily locating and navigating trees of data.
- Support for custom string memory management functions to implement string
pools and other schemes for reducing memory usage.
Mini-XML doesn't do validation or other types of processing on the data
based upon schema files or other sources of definition information.

View File

@ -27,6 +27,8 @@ Mini-XML provides the following functionality:
- Functions for creating and managing trees of data.
- "Find" and "walk" functions for easily locating and navigating trees of
data.
- Support for custom string memory management functions to implement string
pools and other schemes for reducing memory usage.
Mini-XML doesn't do validation or other types of processing on the data based
upon schema files or other sources of definition information.
@ -54,7 +56,7 @@ integrated Mini-XML into Gutenprint and removed libxml2.
Thanks to lots of feedback and support from various developers, Mini-XML has
evolved since then to provide a more complete XML implementation and now stands
at a whopping 3,875 lines of code, compared to 175,808 lines of code for libxml2
at a whopping 3,491 lines of code, compared to 175,808 lines of code for libxml2
version 2.11.7.
@ -103,15 +105,80 @@ proper compiler and linker options for your installation:
Loading an XML File
-------------------
You load an XML file using the [mxmlLoadFile](@@) function:
You load an XML file using the [mxmlLoadFilename](@@) function:
```c
mxml_node_t *
mxmlLoadFilename(mxml_node_t *top, const char *filename,
mxml_load_cb_t load_cb, void *load_cbdata,
mxml_sax_cb_t sax_cb, void *sax_cbdata);
mxmlLoadFilename(mxml_node_t *top, mxml_options_t *options,
const char *filename);
```
Mini-XML also provides functions to load from a `FILE` pointer, a file
descriptor, a string, or using a callback:
```c
mxml_node_t *
mxmlLoadFd(mxml_node_t *top, mxml_options_t *options,
int fd);
mxml_node_t *
mxmlLoadFile(mxml_node_t *top, mxml_options_t *options,
FILE *fp);
mxml_node_t *
mxmlLoadIO(mxml_node_t *top, mxml_options_t *options,
mxml_io_cb_t io_cb, void *io_cbdata);
mxml_node_t *
mxmlLoadString(mxml_node_t *top, mxml_options_t *options,
const char *s);
```
Each accepts a pointer to the top-most ("root") node (usually `NULL`) you want
to add the XML data to, any load options, and the content to be loaded. For
example, the following code will load an XML file called "example.xml" using the
default load options:
```c
mxml_node_t *xml;
xml = mxmlLoadFilename(/*top*/NULL, /*options*/NULL, "example.xml");
```
### Load Options
Load options are specified using a `mxml_options_t` object, which you create
using the [mxmlOptionsNew](@@) function:
```c
mxml_options_t *options = mxmlOptionsNew();
```
The default load options will treat any values in your XML as whitespace-
delimited text (`MXML_TYPE_TEXT`). You can specify a different type of values
using the [mxmlOptionsSetTypeValue](@@) function. For example, the following
will specify that values are opaque text strings, including whitespace
(`MXML_TYPE_OPAQUE`):
```c
mxmlOptionsSetTypeValue(options, MXML_TYPE_OPAQUE);
```
For more complex XML documents, you can specify a callback that returns the type
of value for a given element node using the [mxmlOptionsSetTypeCallback](@@)
function. For example, to specify a callback function called `my_type_cb` that
has no callback data:
```c
mxmlOptionsSetTypeValue(options, my_type_cb, /*cbdata*/NULL);
```
The `my_type_cb` function accepts the callback data pointer (`NULL` in this
case) and the `mxml_node_t` pointer for the current element and returns a
`mxml_type_t` enumeration value specifying the value type for child nodes:
The `load_cb` argument specifies a function that assigns child (value) node
types for each element in the document. The default callback (`NULL`) supports
passing a pointer to an `mxml_type_t` variable containing the type of value
@ -127,28 +194,6 @@ tree = mxmlLoadFilename(/*top*/NULL, "filename.xml",
/*sax_cb*/NULL, /*sax_cbdata*/NULL);
```
Mini-XML also provides functions to load from a `FILE` pointer, a file
descriptor, or string:
```c
mxml_node_t *
mxmlLoadFd(mxml_node_t *top, int fd,
mxml_load_cb_t load_cb, void *load_cbdata,
mxml_sax_cb_t sax_cb, void *sax_cbdata);
mxml_node_t *
mxmlLoadFile(mxml_node_t *top, FILE *fp,
mxml_load_cb_t load_cb, void *load_cbdata,
mxml_sax_cb_t sax_cb, void *sax_cbdata);
mxml_node_t *
mxmlLoadString(mxml_node_t *top, const char *s,
mxml_load_cb_t load_cb, void *load_cbdata,
mxml_sax_cb_t sax_cb, void *sax_cbdata);
```
### Load Callbacks
The `load_xxx` arguments to the mxmlLoadXxx functions are a callback function
and a data pointer which are used to determine the value type of each data node

View File

@ -71,24 +71,13 @@ static int mxml_write_ws(mxml_node_t *node, mxml_options_t *options, mxml_io_cb
// 'mxmlLoadFd()' - Load a file descriptor into an XML node tree.
//
// This function loads the file descriptor `fd` into an XML node tree. The
// nodes in the specified file are added to the specified node `top`. If `NULL`
// is provided, the XML file MUST be well-formed with a single parent processing
// instruction node like `<?xml version="1.0"?>` at the start of the file.
// nodes in the specified file are added to the specified node `top` - if `NULL`
// the XML file MUST be well-formed with a single parent processing instruction
// node like `<?xml version="1.0"?>` at the start of the file.
//
// The load callback function `load_cb` is called to obtain the node type that
// should be used for child nodes. If `NULL`, the `load_cbdata` argument points
// to a `mmd_type_t` variable that specifies the value type or `MMD_TYPE_TEXT`
// if that argument is also `NULL`.
//
// The SAX callback function `sax_cb` and associated callback data `sax_cbdata`
// are used to enable the Simple API for XML streaming mode. The callback is
// called as the XML node tree is parsed.
//
// Note: The most common programming error when using the Mini-XML library is
// to load an XML file using the `MXML_TYPE_TEXT` node type, which returns
// inline text as a series of whitespace-delimited words, instead of using the
// `MXML_TYPE_OPAQUE` node type which returns the inline text as a single string
// (including whitespace).
// Load options are provides via the `options` argument. If `NULL`, all values
// will be loaded into `MXML_TYPE_TEXT` nodes. Use the @link mxmlOptionsNew@
// function to create options when loading XML data.
//
mxml_node_t * // O - First node or `NULL` if the file could not be read.
@ -110,24 +99,13 @@ mxmlLoadFd(
// 'mxmlLoadFile()' - Load a file into an XML node tree.
//
// This function loads the `FILE` pointer `fp` into an XML node tree. The
// nodes in the specified file are added to the specified node `top`. If `NULL`
// is provided, the XML file MUST be well-formed with a single parent processing
// instruction node like `<?xml version="1.0"?>` at the start of the file.
// nodes in the specified file are added to the specified node `top` - if `NULL`
// the XML file MUST be well-formed with a single parent processing instruction
// node like `<?xml version="1.0"?>` at the start of the file.
//
// The load callback function `load_cb` is called to obtain the node type that
// should be used for child nodes. If `NULL`, the `load_cbdata` argument points
// to a `mmd_type_t` variable that specifies the value type or `MMD_TYPE_TEXT`
// if that argument is also `NULL`.
//
// The SAX callback function `sax_cb` and associated callback data `sax_cbdata`
// are used to enable the Simple API for XML streaming mode. The callback is
// called as the XML node tree is parsed.
//
// Note: The most common programming error when using the Mini-XML library is
// to load an XML file using the `MXML_TYPE_TEXT` node type, which returns
// inline text as a series of whitespace-delimited words, instead of using the
// `MXML_TYPE_OPAQUE` node type which returns the inline text as a single string
// (including whitespace).
// Load options are provides via the `options` argument. If `NULL`, all values
// will be loaded into `MXML_TYPE_TEXT` nodes. Use the @link mxmlOptionsNew@
// function to create options when loading XML data.
//
mxml_node_t * // O - First node or `NULL` if the file could not be read.
@ -149,24 +127,13 @@ mxmlLoadFile(
// 'mxmlLoadFilename()' - Load a file into an XML node tree.
//
// This function loads the named file `filename` into an XML node tree. The
// nodes in the specified file are added to the specified node `top`. If `NULL`
// is provided, the XML file MUST be well-formed with a single parent processing
// instruction node like `<?xml version="1.0"?>` at the start of the file.
// nodes in the specified file are added to the specified node `top` - if `NULL`
// the XML file MUST be well-formed with a single parent processing instruction
// node like `<?xml version="1.0"?>` at the start of the file.
//
// The load callback function `load_cb` is called to obtain the node type that
// should be used for child nodes. If `NULL`, the `load_cbdata` argument points
// to a `mmd_type_t` variable that specifies the value type or `MMD_TYPE_TEXT`
// if that argument is also `NULL`.
//
// The SAX callback function `sax_cb` and associated callback data `sax_cbdata`
// are used to enable the Simple API for XML streaming mode. The callback is
// called as the XML node tree is parsed.
//
// Note: The most common programming error when using the Mini-XML library is
// to load an XML file using the `MXML_TYPE_TEXT` node type, which returns
// inline text as a series of whitespace-delimited words, instead of using the
// `MXML_TYPE_OPAQUE` node type which returns the inline text as a single string
// (including whitespace).
// Load options are provides via the `options` argument. If `NULL`, all values
// will be loaded into `MXML_TYPE_TEXT` nodes. Use the @link mxmlOptionsNew@
// function to create options when loading XML data.
//
mxml_node_t * // O - First node or `NULL` if the file could not be read.
@ -201,9 +168,13 @@ mxmlLoadFilename(
// 'mxmlLoadIO()' - Load an XML node tree using a read callback.
//
// This function loads data into an XML node tree using a read callback. The
// nodes in the specified file are added to the specified node `top`. If `NULL`
// is provided, the XML file MUST be well-formed with a single parent processing
// instruction node like `<?xml version="1.0"?>` at the start of the file.
// nodes in the specified file are added to the specified node `top` - if `NULL`
// the XML file MUST be well-formed with a single parent processing instruction
// node like `<?xml version="1.0"?>` at the start of the file.
//
// Load options are provides via the `options` argument. If `NULL`, all values
// will be loaded into `MXML_TYPE_TEXT` nodes. Use the @link mxmlOptionsNew@
// function to create options when loading XML data.
//
// The read callback function `io_cb` is called to read a number of bytes from
// the source. The callback data pointer `io_cbdata` is passed to the read
@ -218,21 +189,6 @@ mxmlLoadFilename(
// }
// ```
//
// The load callback function `load_cb` is called to obtain the node type that
// should be used for child nodes. If `NULL`, the `load_cbdata` argument points
// to a `mmd_type_t` variable that specifies the value type or `MMD_TYPE_TEXT`
// if that argument is also `NULL`.
//
// The SAX callback function `sax_cb` and associated callback data `sax_cbdata`
// are used to enable the Simple API for XML streaming mode. The callback is
// called as the XML node tree is parsed.
//
// Note: The most common programming error when using the Mini-XML library is
// to load an XML file using the `MXML_TYPE_TEXT` node type, which returns
// inline text as a series of whitespace-delimited words, instead of using the
// `MXML_TYPE_OPAQUE` node type which returns the inline text as a single string
// (including whitespace).
//
mxml_node_t * // O - First node or `NULL` if the file could not be read.
mxmlLoadIO(
@ -254,24 +210,13 @@ mxmlLoadIO(
// 'mxmlLoadString()' - Load a string into an XML node tree.
//
// This function loads the string into an XML node tree. The nodes in the
// specified file are added to the specified node `top`. If `NULL` is provided,
// the XML file MUST be well-formed with a single parent processing instruction
// node like `<?xml version="1.0"?>` at the start of the file.
// specified file are added to the specified node `top` - if `NULL` the XML file
// MUST be well-formed with a single parent processing instruction node like
// `<?xml version="1.0"?>` at the start of the file.
//
// The load callback function `load_cb` is called to obtain the node type that
// should be used for child nodes. If `NULL`, the `load_cbdata` argument points
// to a `mmd_type_t` variable that specifies the value type or `MMD_TYPE_TEXT`
// if that argument is also `NULL`.
//
// The SAX callback function `sax_cb` and associated callback data `sax_cbdata`
// are used to enable the Simple API for XML streaming mode. The callback is
// called as the XML node tree is parsed.
//
// Note: The most common programming error when using the Mini-XML library is
// to load an XML file using the `MXML_TYPE_TEXT` node type, which returns
// inline text as a series of whitespace-delimited words, instead of using the
// `MXML_TYPE_OPAQUE` node type which returns the inline text as a single string
// (including whitespace).
// Load options are provides via the `options` argument. If `NULL`, all values
// will be loaded into `MXML_TYPE_TEXT` nodes. Use the @link mxmlOptionsNew@
// function to create options when loading XML data.
//
mxml_node_t * // O - First node or `NULL` if the string has errors.
@ -308,21 +253,9 @@ mxmlLoadString(
// `NULL` is returned if the node would produce an empty string or if the string
// cannot be allocated.
//
// The callback function `save_cb` specifies a function that returns a
// whitespace string or `NULL` before and after each element. The function
// receives the callback data pointer `save_cbdata`, the `mxml_node_t` pointer,
// and a "when" value indicating where the whitespace is being added, for
// example:
//
// ```c
// const char *my_save_cb(void *cbdata, mxml_node_t *node, mxml_ws_t when)
// {
// if (when == MXML_WS_BEFORE_OPEN || when == MXML_WS_AFTER_CLOSE)
// return ("\n");
// else
// return (NULL);
// }
// ```
// Save options are provides via the `options` argument. If `NULL`, the XML
// output will be wrapped at column 72 with no additional whitespace. Use the
// @link mxmlOptionsNew@ function to create options for saving XML data.
//
char * // O - Allocated string or `NULL`
@ -361,21 +294,9 @@ mxmlSaveAllocString(
//
// This function saves the XML tree `node` to a file descriptor.
//
// The callback function `save_cb` specifies a function that returns a
// whitespace string or `NULL` before and after each element. The function
// receives the callback data pointer `save_cbdata`, the `mxml_node_t` pointer,
// and a "when" value indicating where the whitespace is being added, for
// example:
//
// ```c
// const char *my_save_cb(void *cbdata, mxml_node_t *node, mxml_ws_t when)
// {
// if (when == MXML_WS_BEFORE_OPEN || when == MXML_WS_AFTER_CLOSE)
// return ("\n");
// else
// return (NULL);
// }
// ```
// Save options are provides via the `options` argument. If `NULL`, the XML
// output will be wrapped at column 72 with no additional whitespace. Use the
// @link mxmlOptionsNew@ function to create options for saving XML data.
//
bool // O - `true` on success, `false` on error.
@ -406,21 +327,9 @@ mxmlSaveFd(mxml_node_t *node, // I - Node to write
//
// This function saves the XML tree `node` to a stdio `FILE`.
//
// The callback function `save_cb` specifies a function that returns a
// whitespace string or `NULL` before and after each element. The function
// receives the callback data pointer `save_cbdata`, the `mxml_node_t` pointer,
// and a "when" value indicating where the whitespace is being added, for
// example:
//
// ```c
// const char *my_save_cb(void *cbdata, mxml_node_t *node, mxml_ws_t when)
// {
// if (when == MXML_WS_BEFORE_OPEN || when == MXML_WS_AFTER_CLOSE)
// return ("\n");
// else
// return (NULL);
// }
// ```
// Save options are provides via the `options` argument. If `NULL`, the XML
// output will be wrapped at column 72 with no additional whitespace. Use the
// @link mxmlOptionsNew@ function to create options for saving XML data.
//
bool // O - `true` on success, `false` on error.
@ -452,21 +361,9 @@ mxmlSaveFile(
//
// This function saves the XML tree `node` to a named file.
//
// The callback function `save_cb` specifies a function that returns a
// whitespace string or `NULL` before and after each element. The function
// receives the callback data pointer `save_cbdata`, the `mxml_node_t` pointer,
// and a "when" value indicating where the whitespace is being added, for
// example:
//
// ```c
// const char *my_save_cb(void *cbdata, mxml_node_t *node, mxml_ws_t when)
// {
// if (when == MXML_WS_BEFORE_OPEN || when == MXML_WS_AFTER_CLOSE)
// return ("\n");
// else
// return (NULL);
// }
// ```
// Save options are provides via the `options` argument. If `NULL`, the XML
// output will be wrapped at column 72 with no additional whitespace. Use the
// @link mxmlOptionsNew@ function to create options for saving XML data.
//
bool // O - `true` on success, `false` on error.
@ -518,21 +415,9 @@ mxmlSaveFilename(
// }
// ```
//
// The callback function `save_cb` specifies a function that returns a
// whitespace string or `NULL` before and after each element. The function
// receives the callback data pointer `save_cbdata`, the `mxml_node_t` pointer,
// and a "when" value indicating where the whitespace is being added, for
// example:
//
// ```c
// const char *my_save_cb(void *cbdata, mxml_node_t *node, mxml_ws_t when)
// {
// if (when == MXML_WS_BEFORE_OPEN || when == MXML_WS_AFTER_CLOSE)
// return ("\n");
// else
// return (NULL);
// }
// ```
// Save options are provides via the `options` argument. If `NULL`, the XML
// output will be wrapped at column 72 with no additional whitespace. Use the
// @link mxmlOptionsNew@ function to create options for saving XML data.
//
bool // O - `true` on success, `false` on error.
@ -567,23 +452,11 @@ mxmlSaveIO(
//
// 'mxmlSaveString()' - Save an XML node tree to a string.
//
// This function saves the XML tree `node` to a string buffer.
// This function saves the XML tree `node` to a fixed-size string buffer.
//
// The callback function `save_cb` specifies a function that returns a
// whitespace string or `NULL` before and after each element. The function
// receives the callback data pointer `save_cbdata`, the `mxml_node_t` pointer,
// and a "when" value indicating where the whitespace is being added, for
// example:
//
// ```c
// const char *my_save_cb(void *cbdata, mxml_node_t *node, mxml_ws_t when)
// {
// if (when == MXML_WS_BEFORE_OPEN || when == MXML_WS_AFTER_CLOSE)
// return ("\n");
// else
// return (NULL);
// }
// ```
// Save options are provides via the `options` argument. If `NULL`, the XML
// output will be wrapped at column 72 with no additional whitespace. Use the
// @link mxmlOptionsNew@ function to create options for saving XML data.
//
size_t // O - Size of string

View File

@ -27,6 +27,32 @@ mxmlOptionsDelete(
//
// 'mxmlOptionsNew()' - Allocate load/save options.
//
// This function creates a new set of load/save options to use with the
// @link mxmlLoadFd@, @link mxmlLoadFile@, @link mxmlLoadFilename@,
// @link mxmlLoadIO@, @link mxmlLoadString@, @link mxmlSaveAllocString@,
// @link mxmlSaveFd@, @link mxmlSaveFile@, @link mxmlSaveFilename@,
// @link mxmlSaveIO@, and @link mxmlSaveString@ functions. Options can be
// reused for multiple calls to these functions and should be freed using the
// @link mxmlOptionsDelete@ function.
//
// The default load/save options load values using the constant type
// `MXML_TYPE_TEXT` and save XML data with a wrap margin of 72 columns.
// The various `mxmlOptionsSet` functions are used to change the defaults,
// for example:
//
// ```c
// mxml_options_t *options = mxmlOptionsNew();
//
// /* Load values as opaque strings */
// mxmlOptionsSetTypeValue(options, MXML_TYPE_OPAQUE);
// ```
//
// Note: The most common programming error when using the Mini-XML library is
// to load an XML file using the `MXML_TYPE_TEXT` node type, which returns
// inline text as a series of whitespace-delimited words, instead of using the
// `MXML_TYPE_OPAQUE` node type which returns the inline text as a single string
// (including whitespace).
//
mxml_options_t * // O - Options
mxmlOptionsNew(void)
@ -184,8 +210,8 @@ mxmlOptionsSetCustomCallbacks(
// }
// ```
//
// Mini-XML supports the "amp", "gt", "lt", and "quot" character entities, which
// are required by the base XML specification.
// Mini-XML automatically supports the "amp", "gt", "lt", and "quot" character
// entities which are required by the base XML specification.
//
void