32 lines
844 B
C++
32 lines
844 B
C++
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#include <string.h>
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extern "C"
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{
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char** environ = nullptr;
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char* getenv(const char* key)
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{
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char** env = environ;
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size_t len = strlen(key);
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while (*env)
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{
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// Retrieve an environment variable from environ.
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char* var = *(env++);
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// Check for an equals sign, else we just skip this one.
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char* delim = strchr(var, '=');
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if (!delim) continue;
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// Get the length of this variable's key (the part before the equals sign)
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size_t key_length = strcspn(var, "=");
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if (len != key_length) continue;
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// If the keys match, we found it! Return the value (which is just after the equals sign)
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if (!memcmp(key, var, key_length)) { return delim + 1; }
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}
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return nullptr;
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}
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}
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