[dpdk-dev,v5] cfgfile: support looking up sections by index

  This is useful when sections have duplicate names.

Signed-off-by: Rich Lane <rlane@bigswitch.com>
---
v4->v5:
- Reordered sectionname argument.
v3->v4:
- Added section name return value.
- Updated API docs for other functions.
v2->v3
- Added check for index < 0.
v1->v2:
- Added new symbol to version script.

 lib/librte_cfgfile/rte_cfgfile.c           | 18 ++++++++++++++
 lib/librte_cfgfile/rte_cfgfile.h           | 39 ++++++++++++++++++++++++++++++
 lib/librte_cfgfile/rte_cfgfile_version.map |  6 +++++
 3 files changed, 63 insertions(+)
  

> -----Original Message-----
> From: Rich Lane [mailto:rich.lane@bigswitch.com]
> Sent: Monday, February 22, 2016 8:31 PM
> To: dev@dpdk.org
> Cc: Dumitrescu, Cristian <cristian.dumitrescu@intel.com>; Panu Matilainen
> <pmatilai@redhat.com>
> Subject: [PATCH v5] cfgfile: support looking up sections by index
> 
> This is useful when sections have duplicate names.
> 
> Signed-off-by: Rich Lane <rlane@bigswitch.com>
> ---
> v4->v5:
> - Reordered sectionname argument.
> v3->v4:
> - Added section name return value.
> - Updated API docs for other functions.
> v2->v3
> - Added check for index < 0.
> v1->v2:
> - Added new symbol to version script.
> 
>  lib/librte_cfgfile/rte_cfgfile.c           | 18 ++++++++++++++
>  lib/librte_cfgfile/rte_cfgfile.h           | 39
> ++++++++++++++++++++++++++++++
>  lib/librte_cfgfile/rte_cfgfile_version.map |  6 +++++
>  3 files changed, 63 insertions(+)
> 
> diff --git a/lib/librte_cfgfile/rte_cfgfile.c b/lib/librte_cfgfile/rte_cfgfile.c
> index 1cd523f..75625a2 100644
> --- a/lib/librte_cfgfile/rte_cfgfile.c
> +++ b/lib/librte_cfgfile/rte_cfgfile.c
> @@ -333,6 +333,24 @@ rte_cfgfile_section_entries(struct rte_cfgfile *cfg,
> const char *sectionname,
>  	return i;
>  }
> 
> +int
> +rte_cfgfile_section_entries_by_index(struct rte_cfgfile *cfg, int index,
> +		char *sectionname,
> +		struct rte_cfgfile_entry *entries, int max_entries)
> +{
> +	int i;
> +	const struct rte_cfgfile_section *sect;
> +
> +	if (index < 0 || index >= cfg->num_sections)
> +		return -1;
> +
> +	sect = cfg->sections[index];
> +	snprintf(sectionname, CFG_NAME_LEN, "%s", sect->name);
> +	for (i = 0; i < max_entries && i < sect->num_entries; i++)
> +		entries[i] = *sect->entries[i];
> +	return i;
> +}
> +
>  const char *
>  rte_cfgfile_get_entry(struct rte_cfgfile *cfg, const char *sectionname,
>  		const char *entryname)
> diff --git a/lib/librte_cfgfile/rte_cfgfile.h b/lib/librte_cfgfile/rte_cfgfile.h
> index d443782..689fd66 100644
> --- a/lib/librte_cfgfile/rte_cfgfile.h
> +++ b/lib/librte_cfgfile/rte_cfgfile.h
> @@ -126,6 +126,9 @@ int rte_cfgfile_has_section(struct rte_cfgfile *cfg,
> const char *sectionname);
>  /**
>  * Get number of entries in given config file section
>  *
> +* If multiple sections have the given name this function operates on the
> +* first one.
> +*
>  * @param cfg
>  *   Config file
>  * @param sectionname
> @@ -138,6 +141,9 @@ int rte_cfgfile_section_num_entries(struct rte_cfgfile
> *cfg,
> 
>  /** Get section entries as key-value pairs
>  *
> +* If multiple sections have the given name this function operates on the
> +* first one.
> +*
>  * @param cfg
>  *   Config file
>  * @param sectionname
> @@ -155,8 +161,38 @@ int rte_cfgfile_section_entries(struct rte_cfgfile
> *cfg,
>  	struct rte_cfgfile_entry *entries,
>  	int max_entries);
> 
> +/** Get section entries as key-value pairs
> +*
> +* The index of a section is the same as the index of its name in the
> +* result of rte_cfgfile_sections. This API can be used when there are
> +* multiple sections with the same name.
> +*
> +* @param cfg
> +*   Config file
> +* @param index
> +*   Section index
> +* @param entries
> +*   Pre-allocated array of at least max_entries entries where the section
> +*   entries are stored as key-value pair after successful invocation
> +* @param max_entries
> +*   Maximum number of section entries to be stored in entries array

The description for sectionname should also be moved after the description of index parameter to match the argument order. We're nearly there :)

> +* @param sectionname
> +*   Pre-allocated string of at least CFG_NAME_LEN characters where the
> +*   section name is stored after successful invocation.
> +* @return
> +*   Number of entries populated on success, negative error code otherwise
> +*/
> +int rte_cfgfile_section_entries_by_index(struct rte_cfgfile *cfg,
> +	int index,
> +	char *sectionname,
> +	struct rte_cfgfile_entry *entries,
> +	int max_entries);
> +
>  /** Get value of the named entry in named config file section
>  *
> +* If multiple sections have the given name this function operates on the
> +* first one.
> +*
>  * @param cfg
>  *   Config file
>  * @param sectionname
> @@ -172,6 +208,9 @@ const char *rte_cfgfile_get_entry(struct rte_cfgfile
> *cfg,
> 
>  /** Check if given entry exists in named config file section
>  *
> +* If multiple sections have the given name this function operates on the
> +* first one.
> +*
>  * @param cfg
>  *   Config file
>  * @param sectionname
> diff --git a/lib/librte_cfgfile/rte_cfgfile_version.map
> b/lib/librte_cfgfile/rte_cfgfile_version.map
> index bf6c6fd..f6a27a9 100644
> --- a/lib/librte_cfgfile/rte_cfgfile_version.map
> +++ b/lib/librte_cfgfile/rte_cfgfile_version.map
> @@ -13,3 +13,9 @@ DPDK_2.0 {
> 
>  	local: *;
>  };
> +
> +DPDK_2.3 {
> +	global:
> +
> +	rte_cfgfile_section_entries_by_index;
> +} DPDK_2.0;
> --
> 1.9.1