"rpm -qa" C 接口的实现过程

1.rpm -qa 的c代码的实现

这是写死的，仅实现rpm -qa的功能

[main.c]

#include <stdlib.h>
#include <rpmcli.h>
#include <rpmdb.h>
#include <rpmds.h>
#include <rpmts.h>

static struct poptOption optionsTable[]={
{NULL, '\0', POPT_ARG_INCLUDE_TABLE, rpmQVSourcePoptTable, 0,"Query/Verify package selection options:",NULL},
{NULL,'\0',POPT_ARG_INCLUDE_TABLE,rpmcliAllPoptTable,0,"common options for all rpm modes and executables:",NULL},
{NULL,'\0',POPT_ARG_INCLUDE_TABLE,rpmQueryPoptTable,0,"Query options(with -q or --query):",NULL},
{NULL,'\0',POPT_ARG_INCLUDE_TABLE,rpmVerifyPoptTable,0,"Verify options(with -V or --verify):"},
POPT_AUTOALIAS
POPT_AUTOHELP
POPT_TABLEEND

};

int main(int argc,char *argv[])
{
poptContext context;
QVA_t qva=&rpmQVKArgs;
rpmts ts;
int ec, i;
char *const abc[2] = {"rpm1", "-qa"};

context = rpmcliInit(2,abc,optionsTable);
if(context == NULL)
{
poptPrintUsage(context,stderr,0);
exit(EXIT_FAILURE);

}
ts = rpmtsCreate();
         if(qva->qva_mode == 'q')
        {
                if(qva->qva_source != RPMQV_ALL && !poptPeekArg(context))
                {
                        fprintf(stderr,"no argument given for --query");
                        exit(EXIT_FAILURE);
                }

                ec = rpmcliQuery(ts,qva,(ARGV_const_t)poptGetArgs(context));

        }

        else if(qva->qva_mode == 'v')
        {
                rpmVerifyFlags verifyFlags = VERIFY_ALL;
                verifyFlags &= ~qva->qva_flags;
                qva->qva_flags =(rpmQueryFlags)verifyFlags;

                if(qva->qva_source != RPMQV_ALL && !poptPeekArg(context)){

                        fprintf(stderr,"no arguments given for --verify");
                        exit(EXIT_FAILURE);

                }

                ec = rpmcliVerify(ts,qva,(ARGV_const_t)poptGetArgs(context));

        }
        else
        {
                poptPrintUsage(context,stderr,0);
                exit(EXIT_FAILURE);
                                                                                                                                                   
        }

        ts = rpmtsFree(ts);
        context = rpmcliFini(context);
        return ec;

}

编译：gcc  main.c -o main  -I /usr/include/rpm  -lrpm -lrpmio -lpopt

执行：./main

2. rpm [options]的实现

这段代码是活的，可以实现rpm -qa /-qf ......等一些基本功能的实现

#include <stdlib.h>
#include <rpmcli.h>
#include <rpmdb.h>
#include <rpmds.h>
#include <rpmts.h>

static struct poptOption optionsTable[]={
{NULL, '\0', POPT_ARG_INCLUDE_TABLE, rpmQVSourcePoptTable, 0,"Query/Verify package selection options:",NULL},
{NULL,'\0',POPT_ARG_INCLUDE_TABLE,rpmcliAllPoptTable,0,"common options for all rpm modes and executables:",NULL},
{NULL,'\0',POPT_ARG_INCLUDE_TABLE,rpmQueryPoptTable,0,"Query options(with -q or --query):",NULL},
{NULL,'\0',POPT_ARG_INCLUDE_TABLE,rpmVerifyPoptTable,0,"Verify options(with -V or --verify):"},
POPT_AUTOALIAS
POPT_AUTOHELP
POPT_TABLEEND

};

int main(int argc,char *argv[])
{
poptContext context;
QVA_t qva=&rpmQVKArgs;
rpmts ts;
int ec;

context = rpmcliInit(argc,argv,optionsTable);
if(context == NULL)
{
poptPrintUsage(context,stderr,0);
exit(EXIT_FAILURE);

}
ts = rpmtsCreate();
if(qva->qva_mode == 'q')
{
if(qva->qva_source != RPMQV_ALL && !poptPeekArg(context))
{
fprintf(stderr,"no argument given for --query");
exit(EXIT_FAILURE);
}

ec = rpmcliQuery(ts,qva,(ARGV_const_t)poptGetArgs(context));

}

else if(qva->qva_mode == 'v')
{
rpmVerifyFlags verifyFlags = VERIFY_ALL;
verifyFlags &= ~qva->qva_flags;
qva->qva_flags =(rpmQueryFlags)verifyFlags;

if(qva->qva_source != RPMQV_ALL && !poptPeekArg(context)){

fprintf(stderr,"no arguments given for --verify");
exit(EXIT_FAILURE);

}

ec = rpmcliVerify(ts,qva,(ARGV_const_t)poptGetArgs(context));

}
else
{
poptPrintUsage(context,stderr,0);
exit(EXIT_FAILURE);

}

ts = rpmtsFree(ts);
context = rpmcliFini(context);
return ec;

}

编译： gcc main.c -o main -I /usr/include/rpm -lrpm -lrpmio -lpopt

执行： ./main -qa       (可以实现 rpm -qa 的功能，也可传别的参数，读者可自己试验)

3.可供参考的网站：

https://docs.fedoraproject.org/en-US/Fedora_Draft_Documentation/0.1/html/RPM_Guide/ch15s05.html