1 2 /* Two PD getcwd() implementations. 3 Author: Guido van Rossum, CWI Amsterdam, Jan 1991, <guido (at) cwi.nl>. */ 4 5 #include <stdio.h> 6 #include <errno.h> 7 8 #ifdef HAVE_GETWD 9 10 /* Version for BSD systems -- use getwd() */ 11 12 #ifdef HAVE_SYS_PARAM_H 13 #include <sys/param.h> 14 #endif 15 16 #ifndef MAXPATHLEN 17 #if defined(PATH_MAX) && PATH_MAX > 1024 18 #define MAXPATHLEN PATH_MAX 19 #else 20 #define MAXPATHLEN 1024 21 #endif 22 #endif 23 24 extern char *getwd(char *); 25 26 char * 27 getcwd(char *buf, int size) 28 { 29 char localbuf[MAXPATHLEN+1]; 30 char *ret; 31 32 if (size <= 0) { 33 errno = EINVAL; 34 return NULL; 35 } 36 ret = getwd(localbuf); 37 if (ret != NULL && strlen(localbuf) >= (size_t)size) { 38 errno = ERANGE; 39 return NULL; 40 } 41 if (ret == NULL) { 42 errno = EACCES; /* Most likely error */ 43 return NULL; 44 } 45 strncpy(buf, localbuf, size); 46 return buf; 47 } 48 49 #else /* !HAVE_GETWD */ 50 51 /* Version for really old UNIX systems -- use pipe from pwd */ 52 53 #ifndef PWD_CMD 54 #define PWD_CMD "/bin/pwd" 55 #endif 56 57 char * 58 getcwd(char *buf, int size) 59 { 60 FILE *fp; 61 char *p; 62 if (size <= 0) { 63 errno = EINVAL; 64 return NULL; 65 } 66 if ((fp = popen(PWD_CMD, "r")) == NULL) 67 return NULL; 68 if (fgets(buf, size, fp) == NULL || pclose(fp) != 0) { 69 errno = EACCES; /* Most likely error */ 70 return NULL; 71 } 72 for (p = buf; *p != '\n'; p++) { 73 if (*p == '\0') { 74 errno = ERANGE; 75 return NULL; 76 } 77 } 78 *p = '\0'; 79 return buf; 80 } 81 82 #endif /* !HAVE_GETWD */ 83
