* NEWS: Document this. * zic.c (dolink): New arg STAYSYMLINK. All callers changed. If true, use symlink rather than link if the destination is already a symlink. (itsdir): Return 2 if a symlink, for the benefit of dolink. --- NEWS | 5 +++ zic.c | 139 +++++++++++++++++++++++++++++++++--------------------------------- 2 files changed, 75 insertions(+), 69 deletions(-) diff --git a/NEWS b/NEWS index a2a57fc..7f92e17 100644 --- a/NEWS +++ b/NEWS @@ -55,6 +55,11 @@ Unreleased, experimental changes stamps on the reference platform. (Thanks to Alexander Belopolsky for reporting the bug and suggesting a way forward.) + If the installed localtime and/or posixrules files are symbolic + links, zic now keeps them symbolic links when updating them, for + compatibility with platforms like OpenSUSE where other programs + configure these files as symlinks. + zic now avoids hard linking to symbolic links, and avoids some unnecessary mkdir and stat system calls. diff --git a/zic.c b/zic.c index 1c8a193..011b3cc 100644 --- a/zic.c +++ b/zic.c @@ -116,7 +116,7 @@ static int addtype(zic_t, char const *, bool, bool, bool); static void leapadd(zic_t, bool, int, int); static void adjleap(void); static void associate(void); -static void dolink(const char * fromfield, const char * tofield); +static void dolink(const char *, const char *, bool); static char ** getfields(char * buf); static zic_t gethms(const char * string, const char * errstring, bool); @@ -653,7 +653,7 @@ _("%s: More than one -L option specified\n"), */ for (i = 0; i < nlinks; ++i) { eat(links[i].l_filename, links[i].l_linenum); - dolink(links[i].l_from, links[i].l_to); + dolink(links[i].l_from, links[i].l_to, false); if (noise) for (j = 0; j < nlinks; ++j) if (strcmp(links[i].l_to, @@ -662,11 +662,11 @@ _("%s: More than one -L option specified\n"), } if (lcltime != NULL) { eat(_("command line"), 1); - dolink(lcltime, TZDEFAULT); + dolink(lcltime, TZDEFAULT, true); } if (psxrules != NULL) { eat(_("command line"), 1); - dolink(psxrules, TZDEFRULES); + dolink(psxrules, TZDEFRULES, true); } if (warnings && (ferror(stderr) || fclose(stderr) != 0)) return EXIT_FAILURE; @@ -759,12 +759,13 @@ relname(char const *dir, char const *base) } static void -dolink(char const *fromfield, char const *tofield) +dolink(char const *fromfield, char const *tofield, bool staysymlink) { register char * fromname; register char * toname; register int fromisdir; int todirs_made = -1; + int link_errno; fromname = relname(directory, fromfield); toname = relname(directory, tofield); @@ -779,6 +780,8 @@ dolink(char const *fromfield, char const *tofield) progname, fromname, e); exit(EXIT_FAILURE); } + if (staysymlink) + staysymlink = itsdir(toname) == 2; if (remove(toname) == 0) todirs_made = 0; else if (errno != ENOENT) { @@ -786,69 +789,67 @@ dolink(char const *fromfield, char const *tofield) fprintf(stderr, _("%s: Can't remove %s: %s\n"), progname, toname, e); exit(EXIT_FAILURE); } - if (link(fromname, toname) != 0) { - int link_errno = errno; - - if (link_errno == ENOENT && todirs_made < 0) { - todirs_made = mkdirs(toname); - if (todirs_made) - link_errno = link(fromname, toname) == 0 ? 0 : errno; - } - if (link_errno != 0) { - const char *s = fromfield; - const char *t; - char *p; - size_t dotdots = 0; - char *symlinkcontents; - int symlink_result; - - do - t = s; - while ((s = strchr(s, '/')) - && strncmp(fromfield, tofield, ++s - fromfield) == 0); - - for (s = tofield + (t - fromfield); *s; s++) - dotdots += *s == '/'; - symlinkcontents = emalloc(3 * dotdots + strlen(t) + 1); - for (p = symlinkcontents; dotdots-- != 0; p += 3) - memcpy(p, "../", 3); - strcpy(p, t); - symlink_result = symlink(symlinkcontents, toname); - if (symlink_result != 0 && errno == ENOENT - && todirs_made < 0 && mkdirs(toname)) - symlink_result = symlink(symlinkcontents, toname); - free(symlinkcontents); - if (symlink_result == 0) { - if (link_errno != ENOTSUP) - warning(_("symbolic link used because hard link failed: %s"), - strerror (link_errno)); - } else { - FILE *fp, *tp; - int c; - fp = fopen(fromname, "rb"); - if (!fp) { - const char *e = strerror(errno); - fprintf(stderr, - _("%s: Can't read %s: %s\n"), - progname, fromname, e); - exit(EXIT_FAILURE); - } - tp = fopen(toname, "wb"); - if (!tp) { - const char *e = strerror(errno); - fprintf(stderr, - _("%s: Can't create %s: %s\n"), - progname, toname, e); - exit(EXIT_FAILURE); - } - while ((c = getc(fp)) != EOF) - putc(c, tp); - close_file(fp, fromname); - close_file(tp, toname); - if (link_errno != ENOTSUP) - warning(_("copy used because hard link failed: %s"), - strerror (link_errno)); + link_errno = (staysymlink ? ENOTSUP + : link(fromname, toname) == 0 ? 0 : errno); + if (link_errno == ENOENT && todirs_made < 0) { + todirs_made = mkdirs(toname); + if (todirs_made) + link_errno = link(fromname, toname) == 0 ? 0 : errno; + } + if (link_errno != 0) { + const char *s = fromfield; + const char *t; + char *p; + size_t dotdots = 0; + char *symlinkcontents; + int symlink_errno; + + do + t = s; + while ((s = strchr(s, '/')) + && strncmp(fromfield, tofield, ++s - fromfield) == 0); + + for (s = tofield + (t - fromfield); *s; s++) + dotdots += *s == '/'; + symlinkcontents = emalloc(3 * dotdots + strlen(t) + 1); + for (p = symlinkcontents; dotdots-- != 0; p += 3) + memcpy(p, "../", 3); + strcpy(p, t); + symlink_errno = symlink(symlinkcontents, toname) == 0 ? 0 : errno; + if (symlink_errno == ENOENT && todirs_made < 0 && mkdirs(toname)) + symlink_errno = symlink(symlinkcontents, toname) == 0 ? 0 : errno; + free(symlinkcontents); + if (symlink_errno == 0) { + if (link_errno != ENOTSUP) + warning(_("symbolic link used because hard link failed: %s"), + strerror(link_errno)); + } else { + FILE *fp, *tp; + int c; + fp = fopen(fromname, "rb"); + if (!fp) { + char const *e = strerror(errno); + fprintf(stderr, _("%s: Can't read %s: %s\n"), + progname, fromname, e); + exit(EXIT_FAILURE); + } + tp = fopen(toname, "wb"); + if (!tp) { + char const *e = strerror(errno); + fprintf(stderr, _("%s: Can't create %s: %s\n"), + progname, toname, e); + exit(EXIT_FAILURE); } + while ((c = getc(fp)) != EOF) + putc(c, tp); + close_file(fp, fromname); + close_file(tp, toname); + if (link_errno != ENOTSUP) + warning(_("copy used because hard link failed: %s"), + strerror(link_errno)); + else if (symlink_errno != ENOTSUP) + warning(_("copy used because symbolic link failed: %s"), + strerror(symlink_errno)); } } free(fromname); @@ -898,7 +899,7 @@ static const zic_t early_time = (WORK_AROUND_GNOME_BUG_730332 ? BIG_BANG : MINVAL(zic_t, TIME_T_BITS_IN_FILE)); -/* Return 1 if NAME is a directory or a symbolic link, 0 if it's +/* Return 1 if NAME is a directory, 2 if a symbolic link, 0 if something else, -1 (setting errno) if trouble. */ static int itsdir(char const *name) @@ -907,7 +908,7 @@ itsdir(char const *name) int res = lstat(name, &st); if (res == 0) { #ifdef S_ISDIR - return S_ISDIR(st.st_mode) || S_ISLNK(st.st_mode); + return S_ISDIR(st.st_mode) ? 1 : S_ISLNK(st.st_mode) ? 2 : 0; #else char *nameslashdot = relname(name, "."); bool dir = lstat(nameslashdot, &st) == 0; -- 2.7.4