diff options
Diffstat (limited to 'contrib/cvs/src/subr.c')
-rw-r--r-- | contrib/cvs/src/subr.c | 968 |
1 files changed, 968 insertions, 0 deletions
diff --git a/contrib/cvs/src/subr.c b/contrib/cvs/src/subr.c new file mode 100644 index 0000000..faa988a --- /dev/null +++ b/contrib/cvs/src/subr.c @@ -0,0 +1,968 @@ +/* + * Copyright (C) 1986-2005 The Free Software Foundation, Inc. + * + * Portions Copyright (C) 1998-2005 Derek Price, Ximbiot <http://ximbiot.com>, + * and others. + * + * Portions Copyright (C) 1992, Brian Berliner and Jeff Polk + * Portions Copyright (C) 1989-1992, Brian Berliner + * + * You may distribute under the terms of the GNU General Public License as + * specified in the README file that comes with the CVS source distribution. + * + * Various useful functions for the CVS support code. + */ + +#include <assert.h> +#include "cvs.h" +#include "getline.h" + +#ifdef HAVE_NANOSLEEP +# include "xtime.h" +#else /* HAVE_NANOSLEEP */ +# if !defined HAVE_USLEEP && defined HAVE_SELECT + /* use select as a workaround */ +# include "xselect.h" +# endif /* !defined HAVE_USLEEP && defined HAVE_SELECT */ +#endif /* !HAVE_NANOSLEEP */ + +extern char *getlogin (); + +/* + * malloc some data and die if it fails + */ +void * +xmalloc (bytes) + size_t bytes; +{ + char *cp; + + /* Parts of CVS try to xmalloc zero bytes and then free it. Some + systems have a malloc which returns NULL for zero byte + allocations but a free which can't handle NULL, so compensate. */ + if (bytes == 0) + bytes = 1; + + cp = malloc (bytes); + if (cp == NULL) + { + char buf[80]; + sprintf (buf, "out of memory; can not allocate %lu bytes", + (unsigned long) bytes); + error (1, 0, buf); + } + return (cp); +} + +/* + * realloc data and die if it fails [I've always wanted to have "realloc" do + * a "malloc" if the argument is NULL, but you can't depend on it. Here, I + * can *force* it.] + */ +void * +xrealloc (ptr, bytes) + void *ptr; + size_t bytes; +{ + char *cp; + + if (!ptr) + cp = malloc (bytes); + else + cp = realloc (ptr, bytes); + + if (cp == NULL) + { + char buf[80]; + sprintf (buf, "out of memory; can not reallocate %lu bytes", + (unsigned long) bytes); + error (1, 0, buf); + } + return (cp); +} + +/* Two constants which tune expand_string. Having MIN_INCR as large + as 1024 might waste a bit of memory, but it shouldn't be too bad + (CVS used to allocate arrays of, say, 3000, PATH_MAX (8192, often), + or other such sizes). Probably anything which is going to allocate + memory which is likely to get as big as MAX_INCR shouldn't be doing + it in one block which must be contiguous, but since getrcskey does + so, we might as well limit the wasted memory to MAX_INCR or so + bytes. + + MIN_INCR and MAX_INCR should both be powers of two and we generally + try to keep our allocations to powers of two for the most part. + Most malloc implementations these days tend to like that. */ + +#define MIN_INCR 1024 +#define MAX_INCR (2*1024*1024) + +/* *STRPTR is a pointer returned from malloc (or NULL), pointing to *N + characters of space. Reallocate it so that points to at least + NEWSIZE bytes of space. Gives a fatal error if out of memory; + if it returns it was successful. */ +void +expand_string (strptr, n, newsize) + char **strptr; + size_t *n; + size_t newsize; +{ + if (*n < newsize) + { + while (*n < newsize) + { + if (*n < MIN_INCR) + *n = MIN_INCR; + else if (*n >= MAX_INCR) + *n += MAX_INCR; + else + { + *n *= 2; + if (*n > MAX_INCR) + *n = MAX_INCR; + } + } + *strptr = xrealloc (*strptr, *n); + } +} + +/* *STR is a pointer to a malloc'd string. *LENP is its allocated + length. Add SRC to the end of it, reallocating if necessary. */ +void +xrealloc_and_strcat (str, lenp, src) + char **str; + size_t *lenp; + const char *src; +{ + + expand_string (str, lenp, strlen (*str) + strlen (src) + 1); + strcat (*str, src); +} + +/* + * Duplicate a string, calling xmalloc to allocate some dynamic space + */ +char * +xstrdup (str) + const char *str; +{ + char *s; + + if (str == NULL) + return ((char *) NULL); + s = xmalloc (strlen (str) + 1); + (void) strcpy (s, str); + return (s); +} + + + +/* Remove trailing newlines from STRING, destructively. + * + * RETURNS + * + * True if any newlines were removed, false otherwise. + */ +int +strip_trailing_newlines (str) + char *str; +{ + size_t index, origlen; + index = origlen = strlen (str); + + while (index > 0 && str[index-1] == '\n') + str[--index] = '\0'; + + return index != origlen; +} + + + +/* Return the number of levels that PATH ascends above where it starts. + * For example: + * + * "../../foo" -> 2 + * "foo/../../bar" -> 1 + */ +int +pathname_levels (p) + const char *p; +{ + int level; + int max_level; + + if (p == NULL) return 0; + + max_level = 0; + level = 0; + do + { + /* Now look for pathname level-ups. */ + if (p[0] == '.' && p[1] == '.' && (p[2] == '\0' || ISDIRSEP (p[2]))) + { + --level; + if (-level > max_level) + max_level = -level; + } + else if (p[0] == '\0' || ISDIRSEP (p[0]) || + (p[0] == '.' && (p[1] == '\0' || ISDIRSEP (p[1])))) + ; + else + ++level; + + /* q = strchr (p, '/'); but sub ISDIRSEP() for '/': */ + while (*p != '\0' && !ISDIRSEP (*p)) p++; + if (*p != '\0') p++; + } while (*p != '\0'); + return max_level; +} + + + +/* Free a vector, where (*ARGV)[0], (*ARGV)[1], ... (*ARGV)[*PARGC - 1] + are malloc'd and so is *ARGV itself. Such a vector is allocated by + line2argv or expand_wild, for example. */ +void +free_names (pargc, argv) + int *pargc; + char **argv; +{ + register int i; + + for (i = 0; i < *pargc; i++) + { /* only do through *pargc */ + free (argv[i]); + } + free (argv); + *pargc = 0; /* and set it to zero when done */ +} + +/* Convert LINE into arguments separated by SEPCHARS. Set *ARGC + to the number of arguments found, and (*ARGV)[0] to the first argument, + (*ARGV)[1] to the second, etc. *ARGV is malloc'd and so are each of + (*ARGV)[0], (*ARGV)[1], ... Use free_names() to return the memory + allocated here back to the free pool. */ +void +line2argv (pargc, argv, line, sepchars) + int *pargc; + char ***argv; + char *line; + char *sepchars; +{ + char *cp; + /* Could make a case for size_t or some other unsigned type, but + we'll stick with int to avoid signed/unsigned warnings when + comparing with *pargc. */ + int argv_allocated; + + /* Small for testing. */ + argv_allocated = 1; + *argv = (char **) xmalloc (argv_allocated * sizeof (**argv)); + + *pargc = 0; + for (cp = strtok (line, sepchars); cp; cp = strtok ((char *) NULL, sepchars)) + { + if (*pargc == argv_allocated) + { + argv_allocated *= 2; + *argv = xrealloc (*argv, argv_allocated * sizeof (**argv)); + } + (*argv)[*pargc] = xstrdup (cp); + (*pargc)++; + } +} + +/* + * Returns the number of dots ('.') found in an RCS revision number + */ +int +numdots (s) + const char *s; +{ + int dots = 0; + + for (; *s; s++) + { + if (*s == '.') + dots++; + } + return (dots); +} + +/* Compare revision numbers REV1 and REV2 by consecutive fields. + Return negative, zero, or positive in the manner of strcmp. The + two revision numbers must have the same number of fields, or else + compare_revnums will return an inaccurate result. */ +int +compare_revnums (rev1, rev2) + const char *rev1; + const char *rev2; +{ + const char *sp, *tp; + char *snext, *tnext; + int result = 0; + + sp = rev1; + tp = rev2; + while (result == 0) + { + result = strtoul (sp, &snext, 10) - strtoul (tp, &tnext, 10); + if (*snext == '\0' || *tnext == '\0') + break; + sp = snext + 1; + tp = tnext + 1; + } + + return result; +} + +/* Increment a revision number. Working on the string is a bit awkward, + but it avoid problems with integer overflow should the revision numbers + get really big. */ +char * +increment_revnum (rev) + const char *rev; +{ + char *newrev, *p; + size_t len = strlen (rev); + + newrev = xmalloc (len + 2); + memcpy (newrev, rev, len + 1); + for (p = newrev + len; p != newrev; ) + { + --p; + if (!isdigit(*p)) + { + ++p; + break; + } + if (*p != '9') + { + ++*p; + return newrev; + } + *p = '0'; + } + /* The number was all 9s, so change the first character to 1 and add + a 0 to the end. */ + *p = '1'; + p = newrev + len; + *p++ = '0'; + *p = '\0'; + return newrev; +} + +/* Return the username by which the caller should be identified in + CVS, in contexts such as the author field of RCS files, various + logs, etc. */ +char * +getcaller () +{ +#ifndef SYSTEM_GETCALLER + static char *cache; + struct passwd *pw; + uid_t uid; +#endif + + /* If there is a CVS username, return it. */ +#ifdef AUTH_SERVER_SUPPORT + if (CVS_Username != NULL) + return CVS_Username; +#endif + +#ifdef SYSTEM_GETCALLER + return SYSTEM_GETCALLER (); +#else + /* Get the caller's login from his uid. If the real uid is "root" + try LOGNAME USER or getlogin(). If getlogin() and getpwuid() + both fail, return the uid as a string. */ + + if (cache != NULL) + return cache; + + uid = getuid (); + if (uid == (uid_t) 0) + { + char *name; + + /* super-user; try getlogin() to distinguish */ + if (((name = getlogin ()) || (name = getenv("LOGNAME")) || + (name = getenv("USER"))) && *name) + { + cache = xstrdup (name); + return cache; + } + } + if ((pw = (struct passwd *) getpwuid (uid)) == NULL) + { + char uidname[20]; + + (void) sprintf (uidname, "uid%lu", (unsigned long) uid); + cache = xstrdup (uidname); + return cache; + } + cache = xstrdup (pw->pw_name); + return cache; +#endif +} + +#ifdef lint +#ifndef __GNUC__ +/* ARGSUSED */ +time_t +get_date (date, now) + char *date; + struct timeb *now; +{ + time_t foo = 0; + + return (foo); +} +#endif +#endif + + + +/* Given some revision, REV, return the first prior revision that exists in the + * RCS file, RCS. + * + * ASSUMPTIONS + * REV exists. + * + * INPUTS + * RCS The RCS node pointer. + * REV An existing revision in the RCS file referred to by RCS. + * + * RETURNS + * The first prior revision that exists in the RCS file, or NULL if no prior + * revision exists. The caller is responsible for disposing of this string. + * + * NOTES + * This function currently neglects the case where we are on the trunk with + * rev = X.1, where X != 1. If rev = X.Y, where X != 1 and Y > 1, then this + * function should work fine, as revision X.1 must exist, due to RCS rules. + */ +char * +previous_rev (rcs, rev) + RCSNode *rcs; + const char *rev; +{ + char *p; + char *tmp = xstrdup (rev); + long r1; + char *retval; + + /* Our retval can have no more digits and dots than our input revision. */ + retval = xmalloc (strlen (rev) + 1); + p = strrchr (tmp, '.'); + *p = '\0'; + r1 = strtol (p+1, NULL, 10); + do { + if (--r1 == 0) + { + /* If r1 == 0, then we must be on a branch and our parent must + * exist, or we must be on the trunk with a REV like X.1. + * We are neglecting the X.1 with X != 1 case by assuming that + * there is no previous revision when we discover we were on + * the trunk. + */ + p = strrchr (tmp, '.'); + if (p == NULL) + /* We are on the trunk. */ + retval = NULL; + else + { + *p = '\0'; + sprintf (retval, "%s", tmp); + } + break; + } + sprintf (retval, "%s.%ld", tmp, r1); + } while (!RCS_exist_rev (rcs, retval)); + + free (tmp); + return retval; +} + + + +/* Given two revisions, find their greatest common ancestor. If the + two input revisions exist, then rcs guarantees that the gca will + exist. */ + +char * +gca (rev1, rev2) + const char *rev1; + const char *rev2; +{ + int dots; + char *gca, *g; + const char *p1, *p2; + int r1, r2; + char *retval; + + if (rev1 == NULL || rev2 == NULL) + { + error (0, 0, "sanity failure in gca"); + abort(); + } + + /* The greatest common ancestor will have no more dots, and numbers + of digits for each component no greater than the arguments. Therefore + this string will be big enough. */ + g = gca = xmalloc (strlen (rev1) + strlen (rev2) + 100); + + /* walk the strings, reading the common parts. */ + p1 = rev1; + p2 = rev2; + do + { + r1 = strtol (p1, (char **) &p1, 10); + r2 = strtol (p2, (char **) &p2, 10); + + /* use the lowest. */ + (void) sprintf (g, "%d.", r1 < r2 ? r1 : r2); + g += strlen (g); + if (*p1 == '.') ++p1; + else break; + if (*p2 == '.') ++p2; + else break; + } while (r1 == r2); + + /* erase that last dot. */ + *--g = '\0'; + + /* numbers differ, or we ran out of strings. we're done with the + common parts. */ + + dots = numdots (gca); + if (dots == 0) + { + /* revisions differ in trunk major number. */ + + if (r2 < r1) p1 = p2; + if (*p1 == '\0') + { + /* we only got one number. this is strange. */ + error (0, 0, "bad revisions %s or %s", rev1, rev2); + abort(); + } + else + { + /* we have a minor number. use it. */ + *g++ = '.'; + while (*p1 != '.' && *p1 != '\0') + *g++ = *p1++; + *g = '\0'; + } + } + else if ((dots & 1) == 0) + { + /* if we have an even number of dots, then we have a branch. + remove the last number in order to make it a revision. */ + + g = strrchr (gca, '.'); + *g = '\0'; + } + + retval = xstrdup (gca); + free (gca); + return retval; +} + +/* Give fatal error if REV is numeric and ARGC,ARGV imply we are + planning to operate on more than one file. The current directory + should be the working directory. Note that callers assume that we + will only be checking the first character of REV; it need not have + '\0' at the end of the tag name and other niceties. Right now this + is only called from admin.c, but if people like the concept it probably + should also be called from diff -r, update -r, get -r, and log -r. */ + +void +check_numeric (rev, argc, argv) + const char *rev; + int argc; + char **argv; +{ + if (rev == NULL || !isdigit ((unsigned char) *rev)) + return; + + /* Note that the check for whether we are processing more than one + file is (basically) syntactic; that is, we don't behave differently + depending on whether a directory happens to contain only a single + file or whether it contains more than one. I strongly suspect this + is the least confusing behavior. */ + if (argc != 1 + || (!wrap_name_has (argv[0], WRAP_TOCVS) && isdir (argv[0]))) + { + error (0, 0, "while processing more than one file:"); + error (1, 0, "attempt to specify a numeric revision"); + } +} + +/* + * Sanity checks and any required fix-up on message passed to RCS via '-m'. + * RCS 5.7 requires that a non-total-whitespace, non-null message be provided + * with '-m'. Returns a newly allocated, non-empty buffer with whitespace + * stripped from end of lines and end of buffer. + * + * TODO: We no longer use RCS to manage repository files, so maybe this + * nonsense about non-empty log fields can be dropped. + */ +char * +make_message_rcslegal (message) + const char *message; +{ + char *dst, *dp; + const char *mp; + + if (message == NULL) message = ""; + + /* Strip whitespace from end of lines and end of string. */ + dp = dst = (char *) xmalloc (strlen (message) + 1); + for (mp = message; *mp != '\0'; ++mp) + { + if (*mp == '\n') + { + /* At end-of-line; backtrack to last non-space. */ + while (dp > dst && (dp[-1] == ' ' || dp[-1] == '\t')) + --dp; + } + *dp++ = *mp; + } + + /* Backtrack to last non-space at end of string, and truncate. */ + while (dp > dst && isspace ((unsigned char) dp[-1])) + --dp; + *dp = '\0'; + + /* After all that, if there was no non-space in the string, + substitute a non-empty message. */ + if (*dst == '\0') + { + free (dst); + dst = xstrdup ("*** empty log message ***"); + } + + return dst; +} + + + +/* Does the file FINFO contain conflict markers? The whole concept + of looking at the contents of the file to figure out whether there are + unresolved conflicts is kind of bogus (people do want to manage files + which contain those patterns not as conflict markers), but for now it + is what we do. */ +int +file_has_markers (finfo) + const struct file_info *finfo; +{ + FILE *fp; + char *line = NULL; + size_t line_allocated = 0; + int result; + + result = 0; + fp = CVS_FOPEN (finfo->file, "r"); + if (fp == NULL) + error (1, errno, "cannot open %s", finfo->fullname); + while (getline (&line, &line_allocated, fp) > 0) + { + if (strncmp (line, RCS_MERGE_PAT_1, sizeof RCS_MERGE_PAT_1 - 1) == 0 || + strncmp (line, RCS_MERGE_PAT_2, sizeof RCS_MERGE_PAT_2 - 1) == 0 || + strncmp (line, RCS_MERGE_PAT_3, sizeof RCS_MERGE_PAT_3 - 1) == 0) + { + result = 1; + goto out; + } + } + if (ferror (fp)) + error (0, errno, "cannot read %s", finfo->fullname); +out: + if (fclose (fp) < 0) + error (0, errno, "cannot close %s", finfo->fullname); + if (line != NULL) + free (line); + return result; +} + +/* Read the entire contents of the file NAME into *BUF. + If NAME is NULL, read from stdin. *BUF + is a pointer returned from malloc (or NULL), pointing to *BUFSIZE + bytes of space. The actual size is returned in *LEN. On error, + give a fatal error. The name of the file to use in error messages + (typically will include a directory if we have changed directory) + is FULLNAME. MODE is "r" for text or "rb" for binary. */ + +void +get_file (name, fullname, mode, buf, bufsize, len) + const char *name; + const char *fullname; + const char *mode; + char **buf; + size_t *bufsize; + size_t *len; +{ + struct stat s; + size_t nread; + char *tobuf; + FILE *e; + size_t filesize; + + if (name == NULL) + { + e = stdin; + filesize = 100; /* force allocation of minimum buffer */ + } + else + { + /* Although it would be cleaner in some ways to just read + until end of file, reallocating the buffer, this function + does get called on files in the working directory which can + be of arbitrary size, so I think we better do all that + extra allocation. */ + + if (CVS_STAT (name, &s) < 0) + error (1, errno, "can't stat %s", fullname); + + /* Convert from signed to unsigned. */ + filesize = s.st_size; + + e = open_file (name, mode); + } + + if (*buf == NULL || *bufsize <= filesize) + { + *bufsize = filesize + 1; + *buf = xrealloc (*buf, *bufsize); + } + + tobuf = *buf; + nread = 0; + while (1) + { + size_t got; + + got = fread (tobuf, 1, *bufsize - (tobuf - *buf), e); + if (ferror (e)) + error (1, errno, "can't read %s", fullname); + nread += got; + tobuf += got; + + if (feof (e)) + break; + + /* Allocate more space if needed. */ + if (tobuf == *buf + *bufsize) + { + int c; + long off; + + c = getc (e); + if (c == EOF) + break; + off = tobuf - *buf; + expand_string (buf, bufsize, *bufsize + 100); + tobuf = *buf + off; + *tobuf++ = c; + ++nread; + } + } + + if (e != stdin && fclose (e) < 0) + error (0, errno, "cannot close %s", fullname); + + *len = nread; + + /* Force *BUF to be large enough to hold a null terminator. */ + if (nread == *bufsize) + expand_string (buf, bufsize, *bufsize + 1); + (*buf)[nread] = '\0'; +} + + +/* Follow a chain of symbolic links to its destination. FILENAME + should be a handle to a malloc'd block of memory which contains the + beginning of the chain. This routine will replace the contents of + FILENAME with the destination (a real file). */ + +void +resolve_symlink (filename) + char **filename; +{ + if (filename == NULL || *filename == NULL) + return; + + while (islink (*filename)) + { +#ifdef HAVE_READLINK + /* The clean thing to do is probably to have each filesubr.c + implement this (with an error if not supported by the + platform, in which case islink would presumably return 0). + But that would require editing each filesubr.c and so the + expedient hack seems to be looking at HAVE_READLINK. */ + char *newname = xreadlink (*filename); + + if (isabsolute (newname)) + { + free (*filename); + *filename = newname; + } + else + { + const char *oldname = last_component (*filename); + int dirlen = oldname - *filename; + char *fullnewname = xmalloc (dirlen + strlen (newname) + 1); + strncpy (fullnewname, *filename, dirlen); + strcpy (fullnewname + dirlen, newname); + free (newname); + free (*filename); + *filename = fullnewname; + } +#else + error (1, 0, "internal error: islink doesn't like readlink"); +#endif + } +} + +/* + * Rename a file to an appropriate backup name based on BAKPREFIX. + * If suffix non-null, then ".<suffix>" is appended to the new name. + * + * Returns the new name, which caller may free() if desired. + */ +char * +backup_file (filename, suffix) + const char *filename; + const char *suffix; +{ + char *backup_name; + + if (suffix == NULL) + { + backup_name = xmalloc (sizeof (BAKPREFIX) + strlen (filename) + 1); + sprintf (backup_name, "%s%s", BAKPREFIX, filename); + } + else + { + backup_name = xmalloc (sizeof (BAKPREFIX) + + strlen (filename) + + strlen (suffix) + + 2); /* one for dot, one for trailing '\0' */ + sprintf (backup_name, "%s%s.%s", BAKPREFIX, filename, suffix); + } + + if (isfile (filename)) + copy_file (filename, backup_name); + + return backup_name; +} + +/* + * Copy a string into a buffer escaping any shell metacharacters. The + * buffer should be at least twice as long as the string. + * + * Returns a pointer to the terminating NUL byte in buffer. + */ + +char * +shell_escape(buf, str) + char *buf; + const char *str; +{ + static const char meta[] = "$`\\\""; + const char *p; + + for (;;) + { + p = strpbrk(str, meta); + if (!p) p = str + strlen(str); + if (p > str) + { + memcpy(buf, str, p - str); + buf += p - str; + } + if (!*p) break; + *buf++ = '\\'; + *buf++ = *p++; + str = p; + } + *buf = '\0'; + return buf; +} + + + +/* + * We can only travel forwards in time, not backwards. :) + */ +void +sleep_past (desttime) + time_t desttime; +{ + time_t t; + long s; + long us; + + while (time (&t) <= desttime) + { +#ifdef HAVE_GETTIMEOFDAY + struct timeval tv; + gettimeofday (&tv, NULL); + if (tv.tv_sec > desttime) + break; + s = desttime - tv.tv_sec; + if (tv.tv_usec > 0) + us = 1000000 - tv.tv_usec; + else + { + s++; + us = 0; + } +#else + /* default to 20 ms increments */ + s = desttime - t; + us = 20000; +#endif + +#if defined(HAVE_NANOSLEEP) + { + struct timespec ts; + ts.tv_sec = s; + ts.tv_nsec = us * 1000; + (void)nanosleep (&ts, NULL); + } +#elif defined(HAVE_USLEEP) + if (s > 0) + (void)sleep (s); + else + (void)usleep (us); +#elif defined(HAVE_SELECT) + { + /* use select instead of sleep since it is a fairly portable way of + * sleeping for ms. + */ + struct timeval tv; + tv.tv_sec = s; + tv.tv_usec = us; + (void)select (0, (fd_set *)NULL, (fd_set *)NULL, (fd_set *)NULL, + &tv); + } +#else + if (us > 0) s++; + (void)sleep(s); +#endif + } +} + + + +/* Return non-zero iff FILENAME is absolute. + Trivial under Unix, but more complicated under other systems. */ +int +isabsolute (filename) + const char *filename; +{ + return ISABSOLUTE (filename); +} |