--- Makefile.am | 2 + src/shared/rpmvercmp.c | 122 +++++++++++++++++++++++++++++++++++++++++++++++++ src/shared/rpmvercmp.h | 14 ++++++ 3 files changed, 138 insertions(+) create mode 100644 src/shared/rpmvercmp.c create mode 100644 src/shared/rpmvercmp.h
diff --git a/Makefile.am b/Makefile.am index e0813a6..1310a20 100644 --- a/Makefile.am +++ b/Makefile.am @@ -900,6 +900,8 @@ libsystemd_shared_la_SOURCES = \ src/shared/nss-util.h \ src/shared/verbs.c \ src/shared/verbs.h \ + src/shared/rpmvercmp.c \ + src/shared/rpmvercmp.h \ src/shared/sigbus.c \ src/shared/sigbus.h \ src/shared/rbtree.c \ diff --git a/src/shared/rpmvercmp.c b/src/shared/rpmvercmp.c new file mode 100644 index 0000000..c69c2e3 --- /dev/null +++ b/src/shared/rpmvercmp.c @@ -0,0 +1,122 @@ +/* From rpm (Library GPLv2+, which is compatible with LGPLv2.1+) + * git://rpm.org/rpm.git + */ + +#include <stddef.h> +#include <ctype.h> +#include <string.h> + +#include "util.h" +#include "rpmvercmp.h" + +/* compare alpha and numeric segments of two versions */ +/* return 1: a is newer than b */ +/* 0: a and b are the same version */ +/* -1: b is newer than a */ +int rpmvercmp(const char * a, const char * b) +{ + /* easy comparison to see if versions are identical */ + if (streq_ptr(a, b)) return 0; + + char oldch1, oldch2; + char abuf[strlen(a)+1], bbuf[strlen(b)+1]; + char *str1 = abuf, *str2 = bbuf; + char * one, * two; + int rc; + int isnum; + + strcpy(str1, a); + strcpy(str2, b); + + one = str1; + two = str2; + + /* loop through each version segment of str1 and str2 and compare them */ + while (*one || *two) { + while (*one && !isalnum(*one) && *one != '~') one++; + while (*two && !isalnum(*two) && *two != '~') two++; + + /* handle the tilde separator, it sorts before everything else */ + if (*one == '~' || *two == '~') { + if (*one != '~') return 1; + if (*two != '~') return -1; + one++; + two++; + continue; + } + + /* If we ran to the end of either, we are finished with the loop */ + if (!(*one && *two)) break; + + str1 = one; + str2 = two; + + /* grab first completely alpha or completely numeric segment */ + /* leave one and two pointing to the start of the alpha or numeric */ + /* segment and walk str1 and str2 to end of segment */ + if (isdigit(*str1)) { + while (*str1 && isdigit(*str1)) str1++; + while (*str2 && isdigit(*str2)) str2++; + isnum = 1; + } else { + while (*str1 && isalpha(*str1)) str1++; + while (*str2 && isalpha(*str2)) str2++; + isnum = 0; + } + + /* save character at the end of the alpha or numeric segment */ + /* so that they can be restored after the comparison */ + oldch1 = *str1; + *str1 = '\0'; + oldch2 = *str2; + *str2 = '\0'; + + /* this cannot happen, as we previously tested to make sure that */ + /* the first string has a non-null segment */ + if (one == str1) return -1; /* arbitrary */ + + /* take care of the case where the two version segments are */ + /* different types: one numeric, the other alpha (i.e. empty) */ + /* numeric segments are always newer than alpha segments */ + /* XXX See patch #60884 (and details) from bugzilla #50977. */ + if (two == str2) return (isnum ? 1 : -1); + + if (isnum) { + size_t onelen, twolen; + /* this used to be done by converting the digit segments */ + /* to ints using atoi() - it's changed because long */ + /* digit segments can overflow an int - this should fix that. */ + + /* throw away any leading zeros - it's a number, right? */ + while (*one == '0') one++; + while (*two == '0') two++; + + /* whichever number has more digits wins */ + onelen = strlen(one); + twolen = strlen(two); + if (onelen > twolen) return 1; + if (twolen > onelen) return -1; + } + + /* strcmp will return which one is greater - even if the two */ + /* segments are alpha or if they are numeric. don't return */ + /* if they are equal because there might be more segments to */ + /* compare */ + rc = strcmp(one, two); + if (rc) return (rc < 1 ? -1 : 1); + + /* restore character that was replaced by null above */ + *str1 = oldch1; + one = str1; + *str2 = oldch2; + two = str2; + } + + /* this catches the case where all numeric and alpha segments have */ + /* compared identically but the segment sepparating characters were */ + /* different */ + if ((!*one) && (!*two)) return 0; + + /* whichever version still has characters left over wins */ + if (!*one) return -1; else return 1; +} diff --git a/src/shared/rpmvercmp.h b/src/shared/rpmvercmp.h new file mode 100644 index 0000000..4ba6f36 --- /dev/null +++ b/src/shared/rpmvercmp.h @@ -0,0 +1,14 @@ +/* From rpm (Library GPLv2+, which is compatible with LGPLv2.1+) + * git://rpm.org/rpm.git + */ + +#pragma once + +/** \ingroup rpmtrans + * Segmented string compare for version or release strings. + * + * @param a 1st string + * @param b 2nd string + * @return +1 if a is "newer", 0 if equal, -1 if b is "newer" + */ +int rpmvercmp(const char * a, const char * b); -- 2.2.1.209.g41e5f3a _______________________________________________ systemd-devel mailing list systemd-devel@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/systemd-devel