ref: 2f67e21393c25943f25e116fa6912b7d92dbca4e
dir: /sys/src/cmd/python/Python/getcwd.c/
/* Two PD getcwd() implementations. Author: Guido van Rossum, CWI Amsterdam, Jan 1991, <[email protected]>. */ #include <stdio.h> #include <errno.h> #ifdef HAVE_GETWD /* Version for BSD systems -- use getwd() */ #ifdef HAVE_SYS_PARAM_H #include <sys/param.h> #endif #ifndef MAXPATHLEN #if defined(PATH_MAX) && PATH_MAX > 1024 #define MAXPATHLEN PATH_MAX #else #define MAXPATHLEN 1024 #endif #endif extern char *getwd(char *); char * getcwd(char *buf, int size) { char localbuf[MAXPATHLEN+1]; char *ret; if (size <= 0) { errno = EINVAL; return NULL; } ret = getwd(localbuf); if (ret != NULL && strlen(localbuf) >= (size_t)size) { errno = ERANGE; return NULL; } if (ret == NULL) { errno = EACCES; /* Most likely error */ return NULL; } strncpy(buf, localbuf, size); return buf; } #else /* !HAVE_GETWD */ /* Version for really old UNIX systems -- use pipe from pwd */ #ifndef PWD_CMD #define PWD_CMD "/bin/pwd" #endif char * getcwd(char *buf, int size) { FILE *fp; char *p; int sts; if (size <= 0) { errno = EINVAL; return NULL; } if ((fp = popen(PWD_CMD, "r")) == NULL) return NULL; if (fgets(buf, size, fp) == NULL || (sts = pclose(fp)) != 0) { errno = EACCES; /* Most likely error */ return NULL; } for (p = buf; *p != '\n'; p++) { if (*p == '\0') { errno = ERANGE; return NULL; } } *p = '\0'; return buf; } #endif /* !HAVE_GETWD */