{"id":960,"date":"2023-08-22T18:34:12","date_gmt":"2023-08-22T10:34:12","guid":{"rendered":"https:\/\/swordofmorning.com\/?p=960"},"modified":"2025-10-09T13:55:19","modified_gmt":"2025-10-09T05:55:19","slug":"android-sys-v-ipc","status":"publish","type":"post","link":"https:\/\/swordofmorning.com\/index.php\/2023\/08\/22\/android-sys-v-ipc\/","title":{"rendered":"\u5b89\u5353\u5f00\u542fSys V IPC\uff0c\u5e76\u4f7f\u7528\u5171\u4eab\u5185\u5b58\u7f16\u7a0b"},"content":{"rendered":"

\u4e00\u3001\u5b89\u5353\u5f00\u542fSys V IPC<\/h2>\n

1.1 \u914d\u7f6ekernel<\/h3>\n

\u4e3a\u4e86\u5728\u5b89\u5353\u4e0b\u4f7f\u7528shm<\/code>\uff0c\u6211\u4eec\u9700\u8981\u5f00\u542fSys V IPC\u529f\u80fd\uff0c\u9996\u5148\u6211\u4eec\u9700\u8981\u5f00\u542fkernel\u7684general -> Sys V IPC<\/code>\u3002<\/p>\n

1.2 \u4fee\u6539domain.te<\/h3>\n

\u4e4b\u540e\u6211\u4eec\u5c06.\/system\/sepolicy\/public\/domain.te<\/code>\u4e2d\u7684neverallow * *:{ shm sem msg msgq } *;<\/code>\u4fee\u6539\u4e3aneverallow * *:{ sem msg msgq } *;<\/code>\u3002\u8fd9\u91cc\u6839\u636e\u9700\u8981\u79fb\u9664\u5bf9\u5e94\u7684IPC\u9009\u578b\uff0c\u5728\u7f16\u8bd1\u65f6\u6211\u9047\u5230\u4e86\u62a5\u9519\uff0c\u63d0\u793a\u8fd8\u9700\u8981\u4fdd\u6301.\/system\/sepolicy\/prebuilts\/api\/30\/public\/domain.te<\/code>\u548c\u4e0a\u8ff0\u6587\u4ef6\u4e00\u81f4\u3002<\/p>\n

1.3 \u4fee\u6539check_vintf.cpp<\/h3>\n

\u5b89\u5353\u7f16\u8bd1\u7684\u65f6\u5019\u8fd8\u4f1a\u6709\u4e00\u4e2a\u68c0\u67e5\uff0c\u4ee5\u786e\u4fddCONFIG_SYS_V_IPC\u8bbe\u7f6e\u4e3an\uff0c\u4e3a\u4e86\u89c4\u907f\u8fd9\u9879\u68c0\u67e5\uff0c\u6211\u4eec\u9700\u8981\u4fee\u6539.\/system\/libvintf\/check_vintf.cpp<\/code>\u4e2d\u7684\u4ee3\u7801\uff1a<\/p>\n

    if (compat.ok()) {\n        std::cout << "COMPATIBLE" << std::endl;\n        return EX_OK;\n    }\n    if (compat.error().code() == 0) {\n        LOG(ERROR) << "files are incompatible: " << compat.error();\n        std::cout << "INCOMPATIBLE" << std::endl;\n        \/\/ return EX_DATAERR;\n        return EX_OK;\n    }\n    LOG(ERROR) << strerror(compat.error().code()) << ": " << compat.error();\n    return EX_SOFTWARE;<\/code><\/pre>\n
\u8fd9\u91cc\u6211\u4eec\u5c06return EX_DATAERR;<\/code>\u4fee\u6539\u4e3areturn EX_OK;<\/code>\uff0c\u4f46\u662f\u5728\u4fee\u6539\u7684\u65f6\u5019\u9700\u8981\u786e\u4fdd\u4f60\u7684\u7cfb\u7edf\u6ca1\u6709\u5176\u4ed6\u9519\u8bef\u3002\u5efa\u8bae\u5148\u6b63\u5e38\u7f16\u8bd1\u540e\uff0c\u518d\u5f00\u542fSys V IPC\u529f\u80fd\u3002<\/p>\n
\u4e8c\u3001\u4f7f\u7528\u5171\u4eab\u5185\u5b58\u901a\u4fe1<\/h2>\n
2.1 \u53d1\u9001\u8fdb\u7a0b<\/h3>\n
#include <stdio.h>\n#include <stdlib.h>\n#include <string.h>\n#include <sys\/ipc.h>\n#include <sys\/shm.h>\n\nint main() \n{\n    int shmid;\n    char *shmaddr;\n    char message[] = "hello world";\n\n    key_t key1 = ftok("\/data\/local\/tmp\/key\/test_key", 1);\n\n    \/\/ \u521b\u5efa\u5171\u4eab\u5185\u5b58\u6bb5\n    shmid = shmget(key1, sizeof(message), IPC_CREAT | 0666);\n    if (shmid == -1) {\n        perror("shmget");\n        exit(1);\n    }\n\n    \/\/ \u5c06\u5171\u4eab\u5185\u5b58\u8fde\u63a5\u5230\u5f53\u524d\u8fdb\u7a0b\u7684\u5730\u5740\u7a7a\u95f4\n    shmaddr = (char *)shmat(shmid, NULL, 0);\n    if (shmaddr == (char *)(-1)) {\n        perror("shmat");\n        exit(1);\n    }\n\n    \/\/ \u5c06\u6570\u636e\u5199\u5165\u5171\u4eab\u5185\u5b58\n    strcpy(shmaddr, message);\n\n    printf("Message '%s' written to shared memory\\n", message);\n\n    \/\/ \u5206\u79bb\u5171\u4eab\u5185\u5b58\n    shmdt(shmaddr);\n\n    return 0;\n}<\/code><\/pre>\n
2.2 \u63a5\u6536\u8fdb\u7a0b<\/h3>\n
#include <stdio.h>\n#include <stdlib.h>\n#include <string.h>\n#include <sys\/ipc.h>\n#include <sys\/shm.h>\n\nint main() {\n    int shmid;\n    char *shmaddr;\n\n    key_t key1 = ftok("\/data\/local\/tmp\/key\/test_key", 1);\n\n    \/\/ \u83b7\u53d6\u5171\u4eab\u5185\u5b58\u6bb5 12 is sizeof("hello world")\n    shmid = shmget(key1, 12, 0666);\n    if (shmid == -1) {\n        perror("shmget");\n        exit(1);\n    }\n\n    \/\/ \u8fde\u63a5\u5230\u5171\u4eab\u5185\u5b58\u6bb5\n    shmaddr = (char *)shmat(shmid, NULL, 0);\n    if (shmaddr == (char *)(-1)) {\n        perror("shmat");\n        exit(1);\n    }\n\n    \/\/ \u4ece\u5171\u4eab\u5185\u5b58\u8bfb\u53d6\u6570\u636e\u5e76\u6253\u5370\n    printf("Read from shared memory: %s\\n", shmaddr);\n\n    \/\/ \u5206\u79bb\u5171\u4eab\u5185\u5b58\n    shmdt(shmaddr);\n\n    \/\/ \u5220\u9664\u5171\u4eab\u5185\u5b58\u6bb5\uff08\u5728\u5b9e\u9645\u5e94\u7528\u4e2d\uff0c\u53ef\u80fd\u9700\u8981\u8c28\u614e\u5904\u7406\u5220\u9664\u64cd\u4f5c\uff09\n    shmctl(shmid, IPC_RMID, NULL);\n\n    return 0;\n}<\/code><\/pre>\n","protected":false},"excerpt":{"rendered":"
\u4e00\u3001\u5b89\u5353\u5f00\u542fSys V IPC 1.1 \u914d\u7f6ekernel \u4e3a\u4e86\u5728\u5b89\u5353\u4e0b\u4f7f\u7528shm\uff0c\u6211\u4eec\u9700\u8981\u5f00\u542fSys V IPC\u529f\u80fd\uff0c\u9996\u5148\u6211\u4eec\u9700\u8981 …<\/p>","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[45],"tags":[241],"amp_enabled":true,"_links":{"self":[{"href":"https:\/\/swordofmorning.com\/index.php\/wp-json\/wp\/v2\/posts\/960"}],"collection":[{"href":"https:\/\/swordofmorning.com\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/swordofmorning.com\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/swordofmorning.com\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/swordofmorning.com\/index.php\/wp-json\/wp\/v2\/comments?post=960"}],"version-history":[{"count":1,"href":"https:\/\/swordofmorning.com\/index.php\/wp-json\/wp\/v2\/posts\/960\/revisions"}],"predecessor-version":[{"id":961,"href":"https:\/\/swordofmorning.com\/index.php\/wp-json\/wp\/v2\/posts\/960\/revisions\/961"}],"wp:attachment":[{"href":"https:\/\/swordofmorning.com\/index.php\/wp-json\/wp\/v2\/media?parent=960"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/swordofmorning.com\/index.php\/wp-json\/wp\/v2\/categories?post=960"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/swordofmorning.com\/index.php\/wp-json\/wp\/v2\/tags?post=960"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}