{"id":3455,"date":"2025-04-06T00:12:53","date_gmt":"2025-04-05T16:12:53","guid":{"rendered":"https:\/\/www.laixuexila.com\/?p=3455"},"modified":"2025-04-06T00:12:53","modified_gmt":"2025-04-05T16:12:53","slug":"c-%e5%ae%89%e5%85%a8%e5%87%bd%e6%95%b0","status":"publish","type":"post","link":"https:\/\/www.laixuexila.com\/index.php\/2025\/04\/06\/c-%e5%ae%89%e5%85%a8%e5%87%bd%e6%95%b0\/","title":{"rendered":"C \u5b89\u5168\u51fd\u6570"},"content":{"rendered":"\n<p>\u5728 C \u8bed\u8a00\u4e2d\uff0c\u7531\u4e8e\u5176\u5bf9\u5185\u5b58\u7684\u4f4e\u7ea7\u64cd\u4f5c\u80fd\u529b\uff0c<strong>\u5b89\u5168\u95ee\u9898\uff08\u5982\u7f13\u51b2\u533a\u6ea2\u51fa\u3001\u672a\u5b9a\u4e49\u884c\u4e3a\u3001\u683c\u5f0f\u5b57\u7b26\u4e32\u6f0f\u6d1e\u7b49\uff09\u975e\u5e38\u5e38\u89c1<\/strong>\u3002\u4e3a\u4e86\u63d0\u9ad8\u7a0b\u5e8f\u7684\u5065\u58ee\u6027\u548c\u5b89\u5168\u6027\uff0c\u5efa\u8bae\u4f7f\u7528<strong>\u5b89\u5168\u51fd\u6570\uff08safe functions\uff09<\/strong>\u4ee3\u66ff\u4f20\u7edf\u7684\u201c\u5371\u9669\u51fd\u6570\u201d\u3002<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\">1. \u4ec0\u4e48\u662f C \u5b89\u5168\u51fd\u6570\uff1f<\/h2>\n\n\n\n<p>C \u5b89\u5168\u51fd\u6570\u662f\u5728\u8c03\u7528\u65f6<strong>\u663e\u5f0f\u9650\u5236\u5185\u5b58\u8bbf\u95ee\u8303\u56f4<\/strong>\u3001<strong>\u907f\u514d\u7f13\u51b2\u533a\u6ea2\u51fa<\/strong>\u3001<strong>\u683c\u5f0f\u5316\u6f0f\u6d1e<\/strong>\u7b49\u95ee\u9898\u7684\u51fd\u6570\u3002\u8fd9\u4e9b\u51fd\u6570\u4e3b\u8981\u662f\u5bf9\u4f20\u7edf\u6807\u51c6\u5e93\u51fd\u6570\uff08\u5982 <code>strcpy<\/code>, <code>sprintf<\/code>, <code>gets<\/code>\uff09\u7684\u5b89\u5168\u66ff\u4ee3\u3002<\/p>\n\n\n\n<p>\u5e38\u89c1\u5b89\u5168\u51fd\u6570\u6807\u51c6\u5305\u62ec\uff1a<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>C11 \u6807\u51c6 Annex K\uff08\u53ef\u9009\uff09<\/strong><\/li>\n\n\n\n<li><strong>POSIX \u5b89\u5168\u6269\u5c55<\/strong><\/li>\n\n\n\n<li><strong>\u5fae\u8f6f C \u8fd0\u884c\u5e93\u6269\u5c55\uff08\u5982 <code>strcpy_s<\/code>, <code>sprintf_s<\/code>\uff09<\/strong><\/li>\n<\/ul>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\">2. \u5e38\u89c1\u5371\u9669\u51fd\u6570\u4e0e\u5b89\u5168\u66ff\u4ee3<\/h2>\n\n\n\n<figure class=\"wp-block-table\"><table class=\"has-fixed-layout\"><thead><tr><th>\u5371\u9669\u51fd\u6570<\/th><th>\u95ee\u9898<\/th><th>\u63a8\u8350\u5b89\u5168\u66ff\u4ee3<\/th><th>\u8bf4\u660e<\/th><\/tr><\/thead><tbody><tr><td><code>gets()<\/code><\/td><td>\u65e0\u6cd5\u9650\u5236\u8f93\u5165\u957f\u5ea6\uff0c\u6781\u6613\u6ea2\u51fa<\/td><td><code>fgets()<\/code><\/td><td>\u4ece <code>stdin<\/code> \u8bfb\u53d6\u4f46\u9650\u5236\u957f\u5ea6<\/td><\/tr><tr><td><code>strcpy()<\/code><\/td><td>\u4e0d\u68c0\u67e5\u76ee\u6807\u7f13\u51b2\u533a\u5927\u5c0f<\/td><td><code>strncpy()<\/code> \/ <code>strcpy_s()<\/code><\/td><td>\u9650\u5236\u590d\u5236\u7684\u6700\u5927\u5b57\u7b26\u6570<\/td><\/tr><tr><td><code>strcat()<\/code><\/td><td>\u540c\u4e0a<\/td><td><code>strncat()<\/code> \/ <code>strcat_s()<\/code><\/td><td>\u9644\u52a0\u524d\u786e\u4fdd\u4e0d\u6ea2\u51fa<\/td><\/tr><tr><td><code>sprintf()<\/code><\/td><td>\u683c\u5f0f\u5316\u4e0d\u5b89\u5168<\/td><td><code>snprintf()<\/code> \/ <code>sprintf_s()<\/code><\/td><td>\u9650\u5236\u8f93\u51fa\u957f\u5ea6<\/td><\/tr><tr><td><code>scanf(\"%s\", ...)<\/code><\/td><td>\u4e0d\u9650\u5236\u8f93\u5165\u957f\u5ea6<\/td><td><code>scanf(\"%Ns\", ...)<\/code> \/ <code>fgets()<\/code><\/td><td><code>N<\/code> \u4e3a\u6700\u5927\u957f\u5ea6<\/td><\/tr><tr><td><code>memcpy()<\/code><\/td><td>\u5bb9\u6613\u5199\u8d8a\u754c<\/td><td><code>memmove_s()<\/code><\/td><td>\u5e26\u6709\u8fb9\u754c\u68c0\u67e5\uff08\u9700\u5e73\u53f0\u652f\u6301\uff09<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\">3. \u5b89\u5168\u51fd\u6570\u793a\u4f8b\uff08\u63a8\u8350\u5199\u6cd5\uff09<\/h2>\n\n\n\n<h3 class=\"wp-block-heading\">\u2705 \u4f7f\u7528 <code>fgets()<\/code> \u4ee3\u66ff <code>gets()<\/code><\/h3>\n\n\n\n<pre class=\"wp-block-code\"><code>#include &lt;stdio.h&gt;\n\nint main() {\n    char buffer&#91;100];\n    printf(\"\u8bf7\u8f93\u5165\u5b57\u7b26\u4e32\uff1a\");\n    fgets(buffer, sizeof(buffer), stdin); \/\/ \u9650\u5236\u6700\u5927\u8bfb\u53d6\u957f\u5ea6\n    printf(\"\u4f60\u8f93\u5165\u7684\u662f\uff1a%s\", buffer);\n    return 0;\n}<\/code><\/pre>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h3 class=\"wp-block-heading\">\u2705 \u4f7f\u7528 <code>strncpy()<\/code> \u4ee3\u66ff <code>strcpy()<\/code><\/h3>\n\n\n\n<pre class=\"wp-block-code\"><code>#include &lt;string.h&gt;\n\nchar dest&#91;20];\nstrncpy(dest, \"Hello, World!\", sizeof(dest) - 1);\ndest&#91;sizeof(dest) - 1] = '\\0'; \/\/ \u786e\u4fdd\u4ee5 null \u7ed3\u5c3e<\/code><\/pre>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h3 class=\"wp-block-heading\">\u2705 \u4f7f\u7528 <code>snprintf()<\/code> \u4ee3\u66ff <code>sprintf()<\/code><\/h3>\n\n\n\n<pre class=\"wp-block-code\"><code>#include &lt;stdio.h&gt;\n\nchar buffer&#91;50];\nsnprintf(buffer, sizeof(buffer), \"Value is: %d\", 42);<\/code><\/pre>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\">4. \u6743\u5a01\u53c2\u8003\u94fe\u63a5<\/h2>\n\n\n\n<figure class=\"wp-block-table\"><table class=\"has-fixed-layout\"><thead><tr><th>\u5185\u5bb9<\/th><th>\u94fe\u63a5<\/th><\/tr><\/thead><tbody><tr><td>C11 \u5b89\u5168\u51fd\u6570\u6807\u51c6\uff08Annex K\uff09<\/td><td><a href=\"https:\/\/en.cppreference.com\/w\/c\/string\/byte\">https:\/\/en.cppreference.com\/w\/c\/string\/byte<\/a><\/td><\/tr><tr><td>Microsoft \u5b89\u5168\u51fd\u6570\u6587\u6863<\/td><td><a href=\"https:\/\/learn.microsoft.com\/en-us\/cpp\/c-runtime-library\/security-features-in-the-crt\">https:\/\/learn.microsoft.com\/en-us\/cpp\/c-runtime-library\/security-features-in-the-crt<\/a><\/td><\/tr><tr><td>GNU <code>fgets<\/code> \u51fd\u6570\u6587\u6863<\/td><td><a href=\"https:\/\/man7.org\/linux\/man-pages\/man3\/fgets.3.html\">https:\/\/man7.org\/linux\/man-pages\/man3\/fgets.3.html<\/a><\/td><\/tr><tr><td>CERT C \u5b89\u5168\u7f16\u7801\u6807\u51c6<\/td><td><a href=\"https:\/\/wiki.sei.cmu.edu\/confluence\/display\/c\/SEI+CERT+C+Coding+Standard\">https:\/\/wiki.sei.cmu.edu\/confluence\/display\/c\/SEI+CERT+C+Coding+Standard<\/a><\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\">5. \u5b9e\u6218\u5efa\u8bae<\/h2>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>\u603b\u662f\u9650\u5236\u5185\u5b58\u8bbf\u95ee\u957f\u5ea6<\/strong>\uff0c\u54ea\u6015\u4f60\u786e\u5b9a\u4e0d\u4f1a\u6ea2\u51fa\uff1b<\/li>\n\n\n\n<li><strong>\u4f7f\u7528\u73b0\u4ee3\u7f16\u8bd1\u5668\u5f00\u542f\u8b66\u544a\u548c\u9759\u6001\u68c0\u67e5<\/strong>\uff08\u5982 <code>-Wall -Wextra -fsanitize=address<\/code>\uff09\uff1b<\/li>\n\n\n\n<li>\u5982\u679c\u5728 <strong>\u5d4c\u5165\u5f0f\u73af\u5883\u6216\u8de8\u5e73\u53f0\u9879\u76ee\u4e2d<\/strong>\uff0c\u65e0\u6cd5\u4f7f\u7528 <code>*_s()<\/code> \u7cfb\u5217\u51fd\u6570\uff0c\u53ef\u4ee5\u7528 <code>strncpy<\/code>, <code>snprintf<\/code> \u7b49\uff0c\u5e76\u914d\u5408\u65ad\u8a00\u6216\u8fb9\u754c\u68c0\u67e5\uff1b<\/li>\n\n\n\n<li><strong>\u907f\u514d\u81ea\u5df1\u5199\u5b57\u7b26\u4e32\u64cd\u4f5c\u51fd\u6570<\/strong>\uff0c\u9664\u975e\u4f60\u5b8c\u5168\u4e86\u89e3\u5e95\u5c42\u5b9e\u73b0\uff1b<\/li>\n<\/ul>\n","protected":false},"excerpt":{"rendered":"<p>\u5728 C \u8bed\u8a00\u4e2d\uff0c\u7531\u4e8e\u5176\u5bf9\u5185\u5b58\u7684\u4f4e\u7ea7\u64cd\u4f5c\u80fd\u529b\uff0c\u5b89\u5168\u95ee\u9898\uff08\u5982\u7f13\u51b2\u533a\u6ea2\u51fa\u3001\u672a\u5b9a\u4e49\u884c\u4e3a\u3001\u683c\u5f0f\u5b57\u7b26\u4e32\u6f0f\u6d1e\u7b49\uff09\u975e\u5e38\u5e38\u89c1\u3002\u4e3a [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":3456,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[82],"tags":[],"class_list":["post-3455","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-c"],"_links":{"self":[{"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/posts\/3455","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/comments?post=3455"}],"version-history":[{"count":1,"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/posts\/3455\/revisions"}],"predecessor-version":[{"id":3457,"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/posts\/3455\/revisions\/3457"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/media\/3456"}],"wp:attachment":[{"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/media?parent=3455"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/categories?post=3455"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/tags?post=3455"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}