samba 4.0.7 devel 编程之配置篇

之前有段时间在做一个项目，跟samba有关，发现相关的编程资 料很少，都是直接配置的多，codeing的少。所以后来就自己写了一东西。

项目做完后，再来看了一下samba的源码，学习了一下，发现很多东酉都是可以直接调samba相关的库的。现在总结记录下来：

samba 套件中有samba-devel 开发包，samba开发包提供了许多接口，我们可以在代码中调用这些接口来对samba进行操作。

本节想对samba配置文件的操作进行详细的总结一下：

相关函数介绍：

/*************util/talloc_stack.h***************************/
/*
 * Create a new talloc stack frame.
 * 内存分配
 * When free'd, it frees all stack frames that were created after this one and
 * not explicitly freed.
 */
#define talloc_stackframe() _talloc_stackframe(__location__)




/*
 * Get us the current top of the talloc stack.3
 */


#define talloc_tos() _talloc_tos(__location__)
TALLOC_CTX *_talloc_tos(const char *location);


/*
 * return true if a talloc stackframe exists
 * this can be used to prevent memory leaks for code that can
 * optionally use a talloc stackframe (eg. nt_errstr())
 */


bool talloc_stackframe_exists(void);


/*******************param.h*******************************/
/**
 * Initialise the global parameter structure.
初始化（内存）参数上下文
 */
struct loadparm_context *loadparm_init(TALLOC_CTX *mem_ctx); 
struct loadparm_context *loadparm_init_global(bool load_default);


const char *lpcfg_configfile(struct loadparm_context *lp_ctx);
const char *lp_default_path(void);


/**
 * Load the services array from the services file.
 * 用配置文件填充（内存）参数上下文
 * Return True on success, False on failure.
 */
bool lpcfg_load(struct loadparm_context *lp_ctx, const char *filename);
bool lpcfg_load_default(struct loadparm_context *lp_ctx);
/**
 * Return the max number of services.
 * 返回共享服务数目（ [share name] 个数 ）
 */
int lpcfg_numservices(struct loadparm_context *lp_ctx);


/**
 * Display the contents of the services array in human-readable form.
 * 显示当前所有共享的所有参数 ，输出重定向f,show_defaults决定是否显示默认参数
 * 输出的服务数目由maxtoprint决定，
 */
void lpcfg_dump(struct loadparm_context *lp_ctx, FILE *f, bool show_defaults,
    int maxtoprint);
/**
 * Display the contents of one service in human-readable form.
 *显示指定共享(service)的所有参数
 */
void lpcfg_dump_one(FILE *f, bool show_defaults,
struct loadparm_service *service, 
struct loadparm_service *sDefault);
/*
 * 获得指定的共享
 *
*/
struct loadparm_service *lpcfg_servicebynum(struct loadparm_context *lp_ctx,
int snum);
 
struct loadparm_service *lpcfg_service(struct loadparm_context *lp_ctx,
   const char *service_name);

const char *lpcfg_servicename(const struct loadparm_service *service);
/**
 * Display the contents of a single services record.
 * 显示指定共享（service）指定参数(parm_name) 的参数值
 */
bool lpcfg_dump_a_parameter(struct loadparm_context *lp_ctx,
struct loadparm_service *service,
const char *parm_name, FILE * f);
/*
 *设置指定共享（service）的指定参数(ParmName)值(ParmValue)
 *此设置只是在内存中修改，（要保存，需要写入文件） 
*/
bool lpcfg_do_service_parameter(struct loadparm_context *lp_ctx,
    struct loadparm_service *service,
    const char *pszParmName, const char *pszParmValue);
 
/**
 * Process a parameter.
 * 设置全局 属性  ParaName=ParaValue
 */
 bool lpcfg_do_global_parameter(struct loadparm_context *lp_ctx,
   const char *pszParmName, const char *pszParmValue);
bool lpcfg_do_global_parameter_var(struct loadparm_context *lp_ctx,
const char *pszParmName, const char *fmt, ...);
bool lpcfg_set_cmdline(struct loadparm_context *lp_ctx, const char *pszParmName,
   const char *pszParmValue);
bool lpcfg_set_option(struct loadparm_context *lp_ctx, const char *option);


 
/**
 * Return info about the next service  in a service. snum==-1 gives the globals.
 * Return NULL when out of parameters.
 */
struct parm_struct *lpcfg_next_parameter(struct loadparm_context *lp_ctx, int snum, int *i,
     int allparameters);
 
/* The following definitions come from lib/version.c  
 * 显示samba版本号
*/
const char *samba_version_string(void);  




bool lpcfg_is_mydomain(struct loadparm_context *lp_ctx,
    const char *domain);


bool lpcfg_is_my_domain_or_realm(struct loadparm_context *lp_ctx,
     const char *domain);


/**
  see if a string matches either our primary or one of our secondary 
  netbios aliases. do a case insensitive match
*/
bool lpcfg_is_myname(struct loadparm_context *lp_ctx, const char *name);




/*************查询全局属性的值***************/


const char **lpcfg_interfaces(struct loadparm_context *);
const char *lpcfg_realm(struct loadparm_context *);
const char *lpcfg_netbios_name(struct loadparm_context *);
const char *lpcfg_private_dir(struct loadparm_context *);
enum server_role {
ROLE_STANDALONE    = 0,
ROLE_DOMAIN_MEMBER = 1,
ROLE_DOMAIN_BDC    = 2,
ROLE_DOMAIN_PDC    = 3,
/* not in samr.idl */
ROLE_ACTIVE_DIRECTORY_DC = 4,
/* To determine the role automatically, this is not a valid role */
ROLE_AUTO          = 100
};
int lpcfg_server_role(struct loadparm_context *);
int lpcfg_allow_dns_updates(struct loadparm_context *);


bool lpcfg_is_mydomain(struct loadparm_context *lp_ctx,
    const char *domain);
bool lpcfg_is_my_domain_or_realm(struct loadparm_context *lp_ctx,
     const char *domain);
 
bool lpcfg_is_myname(struct loadparm_context *lp_ctx, const char *name);
/*
 *查询指定文件所在的位置（目录）
 *
*/
char *lpcfg_lock_path(TALLOC_CTX* mem_ctx, struct loadparm_context *lp_ctx,
const char *name);
char *lpcfg_config_path(TALLOC_CTX* mem_ctx, struct loadparm_context *lp_ctx,
  const char *name);
char *lpcfg_private_path(TALLOC_CTX* mem_ctx,
   struct loadparm_context *lp_ctx,
   const char *name);
char *smbd_tmp_path(TALLOC_CTX *mem_ctx, 
    struct loadparm_context *lp_ctx,
    const char *name);
/**
 * Return the max print jobs per queue.
 * 查询相关属性的值
 */
int lpcfg_maxprintjobs(struct loadparm_service *service, struct loadparm_service *sDefault);
struct smb_iconv_handle *lpcfg_iconv_handle(struct loadparm_context *lp_ctx);
void lpcfg_smbcli_options(struct loadparm_context *lp_ctx,
struct smbcli_options *options);
void lpcfg_smbcli_session_options(struct loadparm_context *lp_ctx,
struct smbcli_session_options *options);
const char **lpcfg_smb_ports(struct loadparm_context *);
const char *lpcfg_socket_options(struct loadparm_context *);
struct dcerpc_server_info *lpcfg_dcerpc_server_info(TALLOC_CTX *mem_ctx, struct loadparm_context *lp_ctx);
struct gensec_settings *lpcfg_gensec_settings(TALLOC_CTX *, struct loadparm_context *);

例子：viewsamba.c

#include <unistd.h>
#include <stdio.h>
#include <stdint.h>
#include <string.h>
#ifndef __cplusplus
typedef int bool;
#endif
#include <samba_util.h>
#include <util/time.h>
#include <util/talloc_stack.h>
#include <charset.h>
#include <util/data_blob.h>
#include <core/ntstatus.h>
#include <gen_ndr/lsa.h>
#include <gen_ndr/samr.h>
#include <passdb.h>
#include <machine_sid.h>
#include <param.h>
#include <tevent.h>

int main(){
        TALLOC_CTX *frame=talloc_stackframe();   //分配内存
        struct loadparm_context *lp=loadparm_init(frame);  //初始化参数上下文
        FILE*fp=fopen("/root/test/smb.conf","w+");  //用做测试的保存文件
        //load_case_tables();


        lpcfg_load(lp,"/etc/samba/smb.conf");  //加载配置文件
        int num_share=lpcfg_numservices(lp);  //共享服务的数量
        lpcfg_dump(lp,stdout,0,0);  //显示所有配置信自己
        int i=0;


        char *p=lpcfg_realm(lp);  //显示realm 属性的值
        char *name=lpcfg_netbios_name(lp);  //显示netbios名

 char *privatedir=lpcfg_private_dir(lp);    //查询samba的私有目录
        char *smb=lpcfg_configfile(lp);    //查询samba的配置文件
        printf("realm:%s\n netbios name=%s\n privatedir=%s\n",p,name,privatedir);
        printf("smb=%s\n",smb);
        //reload_charcnv(lp);
        //lpcfg_set_cmdline(lp,"vanstor","samba");  //设置global的属性（因为没有 vanstor这个属性，故会出错）


        struct loadparm_service *ser=lpcfg_service(lp,"homes");
        lpcfg_dump_one(stdout,0,ser,ser);  //显示homes共享的所有信息
        lpcfg_dump_a_parameter(lp,ser,"path",stdout); //显示homes共享的path变量信息
        printf("=====================================\n");
        lpcfg_do_service_parameter(lp,ser,"path","/var");  //修改homes共享的path变量值为/var ，但此时还只是在内存中
        lpcfg_dump(lp,fp,0,num_share); //把上面的修改保存到文件
        //printf("samba version :%s\n",samba_version_string());
        //printf("samba default path:%s \n",lp_default_path());
        talloc_stackframe_exists();
}

编译：

gcc -I/usr/include/samba-4.0 -L/usr/lib64/samba -lsamba-hostconfig -lsamba-util -lsmbconf -ltalloc -lsecrets3 -lerrors -o viewsamba viewsamba.c