Initial import
authorGlenn L McGrath <bug1@ihug.co.nz>
Sat, 10 Feb 2001 02:05:24 +0000 (02:05 -0000)
committerGlenn L McGrath <bug1@ihug.co.nz>
Sat, 10 Feb 2001 02:05:24 +0000 (02:05 -0000)
archival/dpkg.c [new file with mode: 0644]
dpkg.c [new file with mode: 0644]

diff --git a/archival/dpkg.c b/archival/dpkg.c
new file mode 100644 (file)
index 0000000..9519eeb
--- /dev/null
@@ -0,0 +1,905 @@
+#include <stdio.h>
+#include <string.h>
+#include <stdlib.h>
+#include <search.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <utime.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include "busybox.h"
+
+//#define PACKAGE "udpkg"
+//#define VERSION "0.1"
+
+/*
+ * Should we do full dependency checking?
+ */
+#define DODEPENDS 1
+
+/*
+ * Should we do debugging?
+ */
+#define DODEBUG 0
+
+#ifdef DODEBUG
+#include <assert.h>
+#define ASSERT(x) assert(x)
+#define SYSTEM(x) do_system(x)
+#define DPRINTF(fmt,args...) fprintf(stderr, fmt, ##args)
+#else
+#define ASSERT(x) /* nothing */
+#define SYSTEM(x) system(x)
+#define DPRINTF(fmt,args...) /* nothing */
+#endif
+
+#define BUFSIZE                4096
+#define ADMINDIR "/var/lib/dpkg"
+#define STATUSFILE     ADMINDIR ## "/status"
+#define DPKGCIDIR      ADMINDIR ## "/tmp.ci/"
+#define INFODIR                ADMINDIR ## "/info/"
+#define UDPKG_QUIET    "UDPKG_QUIET"
+#define DEPENDSMAX     64      /* maximum number of depends we can handle */
+
+#define STATUS_WANTSTART               (0)
+#define STATUS_WANTUNKNOWN             (1 << 0)
+#define STATUS_WANTINSTALL             (1 << 1)
+#define STATUS_WANTHOLD                        (1 << 2)
+#define STATUS_WANTDEINSTALL           (1 << 3)
+#define STATUS_WANTPURGE               (1 << 4)
+#define STATUS_WANTMASK                        ~(STATUS_WANTUNKNOWN | STATUS_WANTINSTALL | STATUS_WANTHOLD | STATUS_WANTDEINSTALL | STATUS_WANTPURGE)
+
+#define STATUS_FLAGSTART               (5)
+#define STATUS_FLAGOK                  (1 << 5)
+#define STATUS_FLAGREINSTREQ           (1 << 6)
+#define STATUS_FLAGHOLD                        (1 << 7)
+#define STATUS_FLAGHOLDREINSTREQ       (1 << 8)
+#define STATUS_FLAGMASK                        ~(STATUS_FLAGOK | STATUS_FLAGREINSTREQ | STATUS_FLAGHOLD | STATUS_FLAGHOLDREINSTREQ)
+
+#define STATUS_STATUSSTART             (9)
+#define STATUS_STATUSNOTINSTALLED      (1 << 9)
+#define STATUS_STATUSUNPACKED          (1 << 10)
+#define STATUS_STATUSHALFCONFIGURED    (1 << 11)
+#define STATUS_STATUSINSTALLED         (1 << 12)
+#define STATUS_STATUSHALFINSTALLED     (1 << 13)
+#define STATUS_STATUSCONFIGFILES       (1 << 14)
+#define STATUS_STATUSPOSTINSTFAILED    (1 << 15)
+#define STATUS_STATUSREMOVALFAILED     (1 << 16)
+#define STATUS_STATUSMASK              ~(STATUS_STATUSNOTINSTALLED | STATUS_STATUSUNPACKED | STATUS_STATUSHALFCONFIGURED | STATUS_STATUSCONFIGFILES | STATUS_STATUSPOSTINSTFAILED | STATUS_STATUSREMOVALFAILED | STATUS_STATUSHALFINSTALLED)
+
+#define COLOR_WHITE                    0
+#define COLOR_GRAY                     1
+#define COLOR_BLACK                    2
+
+/* data structures */
+struct package_t {
+       char *file;
+       char *package;
+       char *version;
+       char *depends;
+       char *provides;
+       char *description;
+       int installer_menu_item;
+       unsigned long status;
+       char color; /* for topo-sort */
+       struct package_t *requiredfor[DEPENDSMAX]; 
+       unsigned short requiredcount;
+       struct package_t *next;
+};
+
+/* function prototypes */
+void *status_read(void);
+void control_read(FILE *f, struct package_t *p);
+int status_merge(void *status, struct package_t *pkgs);
+int package_compare(const void *p1, const void *p2);
+struct package_t *depends_resolve(struct package_t *pkgs, void *status);
+
+#ifdef DODEPENDS
+#include <ctype.h>
+
+static char **depends_split(const char *dependsstr)
+{
+       static char *dependsvec[DEPENDSMAX];
+       char *p;
+       int i = 0;
+
+       dependsvec[0] = 0;
+
+       if (dependsstr != 0)
+       {
+               p = strdup(dependsstr);
+               while (*p != 0 && *p != '\n')
+               {
+                       if (*p != ' ')
+                       {
+                               if (*p == ',')
+                               {
+                                       *p = 0;
+                                       dependsvec[++i] = 0;
+                               }
+                               else if (dependsvec[i] == 0)
+                                       dependsvec[i] = p;
+                       }
+                       else
+                               *p = 0; /* eat the space... */
+                       p++;
+               }
+               *p = 0;
+       }
+       dependsvec[i+1] = 0;
+       return dependsvec;
+}
+
+static void depends_sort_visit(struct package_t **ordered, 
+       struct package_t *pkgs, struct package_t *pkg)
+{
+       /* Topological sort algorithm:
+        * ordered is the output list, pkgs is the dependency graph, pkg is 
+        * the current node
+        *
+        * recursively add all the adjacent nodes to the ordered list, marking
+        * each one as visited along the way
+        *
+        * yes, this algorithm looks a bit odd when all the params have the
+        * same type :-)
+        */
+       unsigned short i;
+
+       /* mark node as processing */
+       pkg->color = COLOR_GRAY;
+
+       /* visit each not-yet-visited node */
+       for (i = 0; i < pkg->requiredcount; i++)
+               if (pkg->requiredfor[i]->color == COLOR_WHITE)
+                       depends_sort_visit(ordered, pkgs, pkg->requiredfor[i]);
+
+#if 0
+       /* add it to the list */
+       newnode = (struct package_t *)malloc(sizeof(struct package_t));
+       /* make a shallow copy */
+       *newnode = *pkg;
+       newnode->next = *ordered;
+       *ordered = newnode;
+#endif
+       pkg->next = *ordered;
+       *ordered = pkg;
+
+       /* mark node as done */
+       pkg->color = COLOR_BLACK;
+}
+
+static struct package_t *depends_sort(struct package_t *pkgs)
+{
+       /* TODO: it needs to break cycles in the to-be-installed package 
+        * graph... */
+       struct package_t *ordered = NULL;
+       struct package_t *pkg;
+
+       for (pkg = pkgs; pkg != 0; pkg = pkg->next)
+               pkg->color = COLOR_WHITE;
+
+       for (pkg = pkgs; pkg != 0; pkg = pkg->next)
+               if (pkg->color == COLOR_WHITE)
+                       depends_sort_visit(&ordered, pkgs, pkg);
+
+       /* Leaks the old list... return the new one... */
+       return ordered;
+}
+
+
+/* resolve package dependencies -- 
+ * for each package in the list of packages to be installed, we parse its 
+ * dependency info to determine if the dependent packages are either 
+ * already installed, or are scheduled to be installed. If both tests fail
+ * than bail.
+ *
+ * The algorithm here is O(n^2*m) where n = number of packages to be 
+ * installed and m is the # of dependencies per package. Not a terribly
+ * efficient algorithm, but given that at any one time you are unlikely
+ * to install a very large number of packages it doesn't really matter
+ */
+struct package_t *depends_resolve(struct package_t *pkgs, void *status)
+{
+       struct package_t *pkg, *chk;
+       struct package_t dependpkg;
+       char **dependsvec;
+       int i;
+       void *found;
+
+       for (pkg = pkgs; pkg != 0; pkg = pkg->next)
+       {
+               dependsvec = depends_split(pkg->depends);
+               i = 0;
+               while (dependsvec[i] != 0)
+               {
+                       /* Check for dependencies; first look for installed packages */
+                       dependpkg.package = dependsvec[i];
+                       if ((found = tfind(&dependpkg, &status, package_compare)) == 0 ||
+                           ((chk = *(struct package_t **)found) &&
+                            (chk->status & (STATUS_FLAGOK | STATUS_STATUSINSTALLED)) != 
+                             (STATUS_FLAGOK | STATUS_STATUSINSTALLED)))
+                       {
+                               /* if it fails, we look through the list of packages we are going to 
+                                * install */
+                               for (chk = pkgs; chk != 0; chk = chk->next)
+                               {
+                                       if (strcmp(chk->package, dependsvec[i]) == 0 ||
+                                           (chk->provides && 
+                                            strncmp(chk->provides, dependsvec[i], strlen(dependsvec[i])) == 0))
+                                       {
+                                               if (chk->requiredcount >= DEPENDSMAX)
+                                               {
+                                                       fprintf(stderr, "Too many dependencies for %s\n", 
+                                                               chk->package);
+                                                       return 0;
+                                               }
+                                               if (chk != pkg)
+                                                       chk->requiredfor[chk->requiredcount++] = pkg;
+                                               break;
+                                       }
+                               }
+                               if (chk == 0)
+                               {
+                                       fprintf(stderr, "%s depends on %s, but it is not going to be installed\n", pkg->package, dependsvec[i]);
+                                       return 0;
+                               }
+                       }
+                       i++;
+               }
+       }
+
+       return depends_sort(pkgs);
+}
+#endif
+
+/* Status file handling routines
+ * 
+ * This is a fairly minimalistic implementation. there are two main functions 
+ * that are supported:
+ * 
+ * 1) reading the entire status file:
+ *    the status file is read into memory as a binary-tree, with just the 
+ *    package and status info preserved
+ *
+ * 2) merging the status file
+ *    control info from (new) packages is merged into the status file, 
+ *    replacing any pre-existing entries. when a merge happens, status info 
+ *    read using the status_read function is written back to the status file
+ */
+
+static const char *statuswords[][10] = {
+       { (char *)STATUS_WANTSTART, "unknown", "install", "hold", 
+               "deinstall", "purge", 0 },
+       { (char *)STATUS_FLAGSTART, "ok", "reinstreq", "hold", 
+               "hold-reinstreq", 0 },
+       { (char *)STATUS_STATUSSTART, "not-installed", "unpacked", "half-configured",
+               "installed", "half-installed",
+               "config-files", "post-inst-failed", 
+               "removal-failed", 0 }
+};
+
+int package_compare(const void *p1, const void *p2)
+{
+       return strcmp(((struct package_t *)p1)->package, 
+               ((struct package_t *)p2)->package);
+}
+
+static unsigned long status_parse(const char *line)
+{
+       char *p;
+       int i, j;
+       unsigned long l = 0;
+       for (i = 0; i < 3; i++)
+       {
+               p = strchr(line, ' ');
+               if (p) *p = 0; 
+               j = 1;
+               while (statuswords[i][j] != 0) 
+               {
+                       if (strcmp(line, statuswords[i][j]) == 0) 
+                       {
+                               l |= (1 << ((int)statuswords[i][0] + j - 1));
+                               break;
+                       }
+                       j++;
+               }
+               if (statuswords[i][j] == 0) return 0; /* parse error */
+               line = p+1;
+       }
+       return l;
+}
+
+static const char *status_print(unsigned long flags)
+{
+       /* this function returns a static buffer... */
+       static char buf[256];
+       int i, j;
+
+       buf[0] = 0;
+       for (i = 0; i < 3; i++)
+       {
+               j = 1;
+               while (statuswords[i][j] != 0)
+               {
+                       if ((flags & (1 << ((int)statuswords[i][0] + j - 1))) != 0)
+                       {
+                               strcat(buf, statuswords[i][j]);
+                               if (i < 2) strcat(buf, " ");
+                               break;
+                       }
+                       j++;
+               }
+               if (statuswords[i][j] == 0)
+               {
+                       fprintf(stderr, "corrupted status flag!!\n");
+                       return NULL;
+               }
+       }
+       return buf;
+}
+
+/*
+ * Read a control file (or a stanza of a status file) and parse it,
+ * filling parsed fields into the package structure
+ */
+void control_read(FILE *f, struct package_t *p)
+{
+       char buf[BUFSIZE];
+       while (fgets(buf, BUFSIZE, f) && !feof(f))
+       {
+               buf[strlen(buf)-1] = 0;
+               if (*buf == 0)
+                       return;
+               else if (strstr(buf, "Package: ") == buf)
+               {
+                       p->package = strdup(buf+9);
+               }
+               else if (strstr(buf, "Status: ") == buf)
+               {
+                       p->status = status_parse(buf+8);
+               }
+               else if (strstr(buf, "Depends: ") == buf)
+               {
+                       p->depends = strdup(buf+9);
+               }
+               else if (strstr(buf, "Provides: ") == buf)
+               {
+                       p->provides = strdup(buf+10);
+               }
+               /* This is specific to the Debian Installer. Ifdef? */
+               else if (strstr(buf, "installer-menu-item: ") == buf) 
+               {
+                       p->installer_menu_item = atoi(buf+21);
+               }
+               else if (strstr(buf, "Description: ") == buf)
+               {
+                       p->description = strdup(buf+13);
+               }
+               /* TODO: localized descriptions */
+       }
+}
+
+void *status_read(void)
+{
+       FILE *f;
+       void *status = 0;
+       struct package_t *m = 0, *p = 0, *t = 0;
+
+       if ((f = fopen(STATUSFILE, "r")) == NULL)
+       {
+               perror(STATUSFILE);
+               return 0;
+       }
+       if (getenv(UDPKG_QUIET) == NULL)
+               printf("(Reading database...)\n");
+       while (!feof(f))
+       {
+               m = (struct package_t *)malloc(sizeof(struct package_t));
+               memset(m, 0, sizeof(struct package_t));
+               control_read(f, m);
+               if (m->package)
+               {
+                       /*
+                        * If there is an item in the tree by this name,
+                        * it must be a virtual package; insert real
+                        * package in preference.
+                        */
+                       tdelete(m, &status, package_compare);
+                       tsearch(m, &status, package_compare);
+                       if (m->provides)
+                       {
+                               /* 
+                                * A "Provides" triggers the insertion
+                                * of a pseudo package into the status
+                                * binary-tree.
+                                */
+                               p = (struct package_t *)malloc(sizeof(struct package_t));
+                               memset(p, 0, sizeof(struct package_t));
+                               p->package = strdup(m->provides);
+
+                               t = *(struct package_t **)tsearch(p, &status, package_compare);
+                               if (!(t == p))
+                               {
+                                       free(p->package);
+                                       free(p);
+                               }
+                               else {
+                                       /*
+                                        * Pseudo package status is the
+                                        * same as the status of the
+                                        * package providing it 
+                                        * FIXME: (not quite right, if 2
+                                        * packages of different statuses
+                                        * provide it).
+                                        */
+                                       t->status = m->status;
+                               }
+                       }
+               }
+               else
+               {
+                       free(m);
+               }
+       }
+       fclose(f);
+       return status;
+}
+
+int status_merge(void *status, struct package_t *pkgs)
+{
+       FILE *fin, *fout;
+       char buf[BUFSIZE];
+       struct package_t *pkg = 0, *statpkg = 0;
+       struct package_t locpkg;
+       int r = 0;
+
+       if ((fin = fopen(STATUSFILE, "r")) == NULL)
+       {
+               perror(STATUSFILE);
+               return 0;
+       }
+       if ((fout = fopen(STATUSFILE ".new", "w")) == NULL)
+       {
+               perror(STATUSFILE ".new");
+               return 0;
+       }
+       if (getenv(UDPKG_QUIET) == NULL)
+               printf("(Updating database...)\n");
+       while (fgets(buf, BUFSIZE, fin) && !feof(fin))
+       {
+               buf[strlen(buf)-1] = 0; /* trim newline */
+               /* If we see a package header, find out if it's a package
+                * that we have processed. if so, we skip that block for
+                * now (write it at the end).
+                *
+                * we also look at packages in the status cache and update
+                * their status fields
+                */
+               if (strstr(buf, "Package: ") == buf)
+               {
+                       for (pkg = pkgs; pkg != 0 && strncmp(buf+9,
+                                       pkg->package, strlen(pkg->package))!=0;
+                            pkg = pkg->next) ;
+
+                       locpkg.package = buf+9;
+                       statpkg = tfind(&locpkg, &status, package_compare);
+                       
+                       /* note: statpkg should be non-zero, unless the status
+                        * file was changed while we are processing (no locking
+                        * is currently done...
+                        */
+                       if (statpkg != 0) statpkg = *(struct package_t **)statpkg;
+               }
+               if (pkg != 0) continue;
+
+               if (strstr(buf, "Status: ") == buf && statpkg != 0)
+               {
+                         snprintf(buf, sizeof(buf), "Status: %s",
+                                status_print(statpkg->status));
+               }
+               fputs(buf, fout);
+               fputc('\n', fout);
+       }
+
+       // Print out packages we processed.
+       for (pkg = pkgs; pkg != 0; pkg = pkg->next) {
+               fprintf(fout, "Package: %s\nStatus: %s\n", 
+                       pkg->package, status_print(pkg->status));
+               if (pkg->depends)
+                       fprintf(fout, "Depends: %s\n", pkg->depends);
+               if (pkg->provides)
+                       fprintf(fout, "Provides: %s\n", pkg->provides);
+               if (pkg->installer_menu_item)
+                       fprintf(fout, "installer-menu-item: %i\n", pkg->installer_menu_item);
+               if (pkg->description)
+                       fprintf(fout, "Description: %s\n", pkg->description);
+               fputc('\n', fout);
+       }
+       
+       fclose(fin);
+       fclose(fout);
+
+       r = rename(STATUSFILE, STATUSFILE ".bak");
+       if (r == 0) r = rename(STATUSFILE ".new", STATUSFILE);
+       return 0;
+}
+
+#include <errno.h>
+#include <fcntl.h>
+#include <search.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <utime.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+
+/* 
+ * Main udpkg implementation routines
+ */
+
+#ifdef DODEBUG
+static int do_system(const char *cmd)
+{
+       DPRINTF("cmd is %s\n", cmd);
+       return system(cmd);
+}
+#else
+#define do_system(cmd) system(cmd)
+#endif
+
+static int is_file(const char *fn)
+{
+       struct stat statbuf;
+
+       if (stat(fn, &statbuf) < 0) return 0;
+       return S_ISREG(statbuf.st_mode);
+}
+
+static int dpkg_copyfile(const char *src, const char *dest)
+{
+       /* copy a (regular) file if it exists, preserving the mode, mtime 
+        * and atime */
+       char buf[8192];
+       int infd, outfd;
+       int r;
+       struct stat srcStat;
+       struct utimbuf times;
+
+       if (stat(src, &srcStat) < 0) 
+       {
+               if (errno == 2) return 0; else return -1;
+       }
+       if ((infd = open(src, O_RDONLY)) < 0) 
+               return -1;
+       if ((outfd = open(dest, O_WRONLY|O_CREAT|O_TRUNC, srcStat.st_mode)) < 0)
+               return -1;
+       while ((r = read(infd, buf, sizeof(buf))) > 0)
+       {
+               if (write(outfd, buf, r) < 0)
+                       return -1;
+       }
+       close(outfd);
+       close(infd);
+       if (r < 0) return -1;
+       times.actime = srcStat.st_atime;
+       times.modtime = srcStat.st_mtime;
+       if (utime(dest, &times) < 0) return -1;
+       return 1;
+}
+
+static int dpkg_doconfigure(struct package_t *pkg)
+{
+       int r;
+       char postinst[1024];
+       char buf[1024];
+       DPRINTF("Configuring %s\n", pkg->package);
+       pkg->status &= STATUS_STATUSMASK;
+       snprintf(postinst, sizeof(postinst), "%s%s.postinst", INFODIR, pkg->package);
+       if (is_file(postinst))
+       {
+               snprintf(buf, sizeof(buf), "%s configure", postinst);
+               if ((r = do_system(buf)) != 0)
+               {
+                       fprintf(stderr, "postinst exited with status %d\n", r);
+                       pkg->status |= STATUS_STATUSHALFCONFIGURED;
+                       return 1;
+               }
+       }
+
+       pkg->status |= STATUS_STATUSINSTALLED;
+       
+       return 0;
+}
+
+static int dpkg_dounpack(struct package_t *pkg)
+{
+       int r = 0;
+       char *cwd, *p;
+       FILE *infp, *outfp;
+       char buf[1024], buf2[1024];
+       int i;
+       char *adminscripts[] = { "prerm", "postrm", "preinst", "postinst",
+                                "conffiles", "md5sums", "shlibs", 
+                                "templates" };
+
+       DPRINTF("Unpacking %s\n", pkg->package);
+
+       cwd = getcwd(0, 0);
+       chdir("/");
+       snprintf(buf, sizeof(buf), "ar -p %s data.tar.gz|zcat|tar -xf -", pkg->file);
+       if (SYSTEM(buf) == 0)
+       {
+               /* Installs the package scripts into the info directory */
+               for (i = 0; i < sizeof(adminscripts) / sizeof(adminscripts[0]);
+                    i++)
+               {
+                       snprintf(buf, sizeof(buf), "%s%s/%s",
+                               DPKGCIDIR, pkg->package, adminscripts[i]);
+                       snprintf(buf2, sizeof(buf), "%s%s.%s", 
+                               INFODIR, pkg->package, adminscripts[i]);
+                       if (dpkg_copyfile(buf, buf2) < 0)
+                       {
+                               fprintf(stderr, "Cannot copy %s to %s: %s\n", 
+                                       buf, buf2, strerror(errno));
+                               r = 1;
+                               break;
+                       }
+                       else
+                       {
+                               /* ugly hack to create the list file; should
+                                * probably do something more elegant
+                                *
+                                * why oh why does dpkg create the list file
+                                * so oddly...
+                                */
+                               snprintf(buf, sizeof(buf), 
+                                       "ar -p %s data.tar.gz|zcat|tar -tf -", 
+                                       pkg->file);
+                               snprintf(buf2, sizeof(buf2),
+                                       "%s%s.list", INFODIR, pkg->package);
+                               if ((infp = popen(buf, "r")) == NULL ||
+                                   (outfp = fopen(buf2, "w")) == NULL)
+                               {
+                                       fprintf(stderr, "Cannot create %s\n",
+                                               buf2);
+                                       r = 1;
+                                       break;
+                               }
+                               while (fgets(buf, sizeof(buf), infp) &&
+                                      !feof(infp))
+                               {
+                                       p = buf;
+                                       if (*p == '.') p++;
+                                       if (*p == '/' && *(p+1) == '\n')
+                                       {
+                                               *(p+1) = '.';
+                                               *(p+2) = '\n';
+                                               *(p+3) = 0;
+                                       }
+                                       if (p[strlen(p)-2] == '/')
+                                       {
+                                               p[strlen(p)-2] = '\n';
+                                               p[strlen(p)-1] = 0;
+                                       }
+                                       fputs(p, outfp);
+                               }
+                               fclose(infp);
+                               fclose(outfp);
+                       }
+               }
+               pkg->status &= STATUS_WANTMASK;
+               pkg->status |= STATUS_WANTINSTALL;
+               pkg->status &= STATUS_FLAGMASK;
+               pkg->status |= STATUS_FLAGOK;
+               pkg->status &= STATUS_STATUSMASK;
+               if (r == 0)
+                       pkg->status |= STATUS_STATUSUNPACKED;
+               else
+                       pkg->status |= STATUS_STATUSHALFINSTALLED;
+       }
+       chdir(cwd);
+       return r;
+}
+
+static int dpkg_doinstall(struct package_t *pkg)
+{
+       DPRINTF("Installing %s\n", pkg->package);
+       return (dpkg_dounpack(pkg) || dpkg_doconfigure(pkg));
+}
+
+static int dpkg_unpackcontrol(struct package_t *pkg)
+{
+       int r = 1;
+       char *cwd = 0;
+       char *p;
+       char buf[1024];
+       FILE *f;
+
+       p = strrchr(pkg->file, '/');
+       if (p) p++; else p = pkg->file;
+       p = pkg->package = strdup(p);
+       while (*p != 0 && *p != '_' && *p != '.') p++;
+       *p = 0;
+
+       cwd = getcwd(0, 0);
+       snprintf(buf, sizeof(buf), "%s%s", DPKGCIDIR, pkg->package);
+       DPRINTF("dir = %s\n", buf);
+       if (mkdir(buf, S_IRWXU) == 0 && chdir(buf) == 0)
+       {
+               snprintf(buf, sizeof(buf), "ar -p %s control.tar.gz|zcat|tar -xf -",
+                       pkg->file);
+               if (SYSTEM(buf) == 0)
+               {
+                       if ((f = fopen("control", "r")) != NULL) {
+                               control_read(f, pkg);
+                               r = 0;
+                       }
+               }
+       }
+
+       chdir(cwd);
+       free(cwd);
+       return r;
+}
+
+static int dpkg_unpack(struct package_t *pkgs)
+{
+       int r = 0;
+       struct package_t *pkg;
+       void *status = status_read();
+
+       if (SYSTEM("rm -rf -- " DPKGCIDIR) != 0 ||
+           mkdir(DPKGCIDIR, S_IRWXU) != 0)
+       {
+               perror("mkdir");
+               return 1;
+       }
+       
+       for (pkg = pkgs; pkg != 0; pkg = pkg->next)
+       {
+               dpkg_unpackcontrol(pkg);
+               r = dpkg_dounpack(pkg);
+               if (r != 0) break;
+       }
+       status_merge(status, pkgs);
+       SYSTEM("rm -rf -- " DPKGCIDIR);
+       return r;
+}
+
+static int dpkg_configure(struct package_t *pkgs)
+{
+       int r = 0;
+       void *found;
+       struct package_t *pkg;
+       void *status = status_read();
+       for (pkg = pkgs; pkg != 0 && r == 0; pkg = pkg->next)
+       {
+               found = tfind(pkg, &status, package_compare);
+               if (found == 0)
+               {
+                       fprintf(stderr, "Trying to configure %s, but it is not installed\n", pkg->package);
+                       r = 1;
+               }
+               else
+               {
+                       /* configure the package listed in the status file;
+                        * not pkg, as we have info only for the latter */
+                       r = dpkg_doconfigure(*(struct package_t **)found);
+               }
+       }
+       status_merge(status, 0);
+       return r;
+}
+
+static int dpkg_install(struct package_t *pkgs)
+{
+       struct package_t *p, *ordered = 0;
+       void *status = status_read();
+       if (SYSTEM("rm -rf -- " DPKGCIDIR) != 0 ||
+           mkdir(DPKGCIDIR, S_IRWXU) != 0)
+       {
+               perror("mkdir");
+               return 1;
+       }
+       
+       /* Stage 1: parse all the control information */
+       for (p = pkgs; p != 0; p = p->next)
+               if (dpkg_unpackcontrol(p) != 0)
+               {
+                       perror(p->file);
+                       /* force loop break, and prevents further ops */
+                       pkgs = 0;
+               }
+       
+       /* Stage 2: resolve dependencies */
+#ifdef DODEPENDS
+       ordered = depends_resolve(pkgs, status);
+#else
+       ordered = pkgs;
+#endif
+       
+       /* Stage 3: install */
+       for (p = ordered; p != 0; p = p->next)
+       {
+               p->status &= STATUS_WANTMASK;
+               p->status |= STATUS_WANTINSTALL;
+
+               /* for now the flag is always set to ok... this is probably
+                * not what we want
+                */
+               p->status &= STATUS_FLAGMASK;
+               p->status |= STATUS_FLAGOK;
+
+               if (dpkg_doinstall(p) != 0)
+               {
+                       perror(p->file);
+               }
+       }
+       
+       if (ordered != 0)
+               status_merge(status, pkgs);
+       SYSTEM("rm -rf -- " DPKGCIDIR);
+       return 0;
+}
+
+static int dpkg_remove(struct package_t *pkgs)
+{
+       struct package_t *p;
+       void *status = status_read();
+       for (p = pkgs; p != 0; p = p->next)
+       {
+       }
+       status_merge(status, 0);
+       return 0;
+}
+
+int dpkg_main(int argc, char **argv)
+{
+       char opt = 0;
+       char *s;
+       struct package_t *p, *packages = NULL;
+       char *cwd = getcwd(0, 0);
+       while (*++argv)
+       {
+               if (**argv == '-') {
+                       /* Nasty little hack to "parse" long options. */
+                       s = *argv;
+                       while (*s == '-')
+                               s++;
+                       opt=s[0];
+               }
+               else
+               {
+                       p = (struct package_t *)malloc(sizeof(struct package_t));
+                       memset(p, 0, sizeof(struct package_t));
+                       if (**argv == '/')
+                               p->file = *argv;
+                       else if (opt != 'c')
+                       {
+                               p->file = malloc(strlen(cwd) + strlen(*argv) + 2);
+                               sprintf(p->file, "%s/%s", cwd, *argv);
+                       }
+                       else {
+                               p->package = strdup(*argv);
+                       }
+                       p->next = packages;
+                       packages = p;
+               }
+                       
+       }
+       switch (opt)
+       {
+               case 'i': return dpkg_install(packages); break;
+               case 'r': return dpkg_remove(packages); break;
+               case 'u': return dpkg_unpack(packages); break;
+               case 'c': return dpkg_configure(packages); break;
+       }
+
+       /* if it falls through to here, some of the command line options were
+          wrong */
+       usage(dpkg_usage);
+       return 0;
+}
\ No newline at end of file
diff --git a/dpkg.c b/dpkg.c
new file mode 100644 (file)
index 0000000..9519eeb
--- /dev/null
+++ b/dpkg.c
@@ -0,0 +1,905 @@
+#include <stdio.h>
+#include <string.h>
+#include <stdlib.h>
+#include <search.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <utime.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include "busybox.h"
+
+//#define PACKAGE "udpkg"
+//#define VERSION "0.1"
+
+/*
+ * Should we do full dependency checking?
+ */
+#define DODEPENDS 1
+
+/*
+ * Should we do debugging?
+ */
+#define DODEBUG 0
+
+#ifdef DODEBUG
+#include <assert.h>
+#define ASSERT(x) assert(x)
+#define SYSTEM(x) do_system(x)
+#define DPRINTF(fmt,args...) fprintf(stderr, fmt, ##args)
+#else
+#define ASSERT(x) /* nothing */
+#define SYSTEM(x) system(x)
+#define DPRINTF(fmt,args...) /* nothing */
+#endif
+
+#define BUFSIZE                4096
+#define ADMINDIR "/var/lib/dpkg"
+#define STATUSFILE     ADMINDIR ## "/status"
+#define DPKGCIDIR      ADMINDIR ## "/tmp.ci/"
+#define INFODIR                ADMINDIR ## "/info/"
+#define UDPKG_QUIET    "UDPKG_QUIET"
+#define DEPENDSMAX     64      /* maximum number of depends we can handle */
+
+#define STATUS_WANTSTART               (0)
+#define STATUS_WANTUNKNOWN             (1 << 0)
+#define STATUS_WANTINSTALL             (1 << 1)
+#define STATUS_WANTHOLD                        (1 << 2)
+#define STATUS_WANTDEINSTALL           (1 << 3)
+#define STATUS_WANTPURGE               (1 << 4)
+#define STATUS_WANTMASK                        ~(STATUS_WANTUNKNOWN | STATUS_WANTINSTALL | STATUS_WANTHOLD | STATUS_WANTDEINSTALL | STATUS_WANTPURGE)
+
+#define STATUS_FLAGSTART               (5)
+#define STATUS_FLAGOK                  (1 << 5)
+#define STATUS_FLAGREINSTREQ           (1 << 6)
+#define STATUS_FLAGHOLD                        (1 << 7)
+#define STATUS_FLAGHOLDREINSTREQ       (1 << 8)
+#define STATUS_FLAGMASK                        ~(STATUS_FLAGOK | STATUS_FLAGREINSTREQ | STATUS_FLAGHOLD | STATUS_FLAGHOLDREINSTREQ)
+
+#define STATUS_STATUSSTART             (9)
+#define STATUS_STATUSNOTINSTALLED      (1 << 9)
+#define STATUS_STATUSUNPACKED          (1 << 10)
+#define STATUS_STATUSHALFCONFIGURED    (1 << 11)
+#define STATUS_STATUSINSTALLED         (1 << 12)
+#define STATUS_STATUSHALFINSTALLED     (1 << 13)
+#define STATUS_STATUSCONFIGFILES       (1 << 14)
+#define STATUS_STATUSPOSTINSTFAILED    (1 << 15)
+#define STATUS_STATUSREMOVALFAILED     (1 << 16)
+#define STATUS_STATUSMASK              ~(STATUS_STATUSNOTINSTALLED | STATUS_STATUSUNPACKED | STATUS_STATUSHALFCONFIGURED | STATUS_STATUSCONFIGFILES | STATUS_STATUSPOSTINSTFAILED | STATUS_STATUSREMOVALFAILED | STATUS_STATUSHALFINSTALLED)
+
+#define COLOR_WHITE                    0
+#define COLOR_GRAY                     1
+#define COLOR_BLACK                    2
+
+/* data structures */
+struct package_t {
+       char *file;
+       char *package;
+       char *version;
+       char *depends;
+       char *provides;
+       char *description;
+       int installer_menu_item;
+       unsigned long status;
+       char color; /* for topo-sort */
+       struct package_t *requiredfor[DEPENDSMAX]; 
+       unsigned short requiredcount;
+       struct package_t *next;
+};
+
+/* function prototypes */
+void *status_read(void);
+void control_read(FILE *f, struct package_t *p);
+int status_merge(void *status, struct package_t *pkgs);
+int package_compare(const void *p1, const void *p2);
+struct package_t *depends_resolve(struct package_t *pkgs, void *status);
+
+#ifdef DODEPENDS
+#include <ctype.h>
+
+static char **depends_split(const char *dependsstr)
+{
+       static char *dependsvec[DEPENDSMAX];
+       char *p;
+       int i = 0;
+
+       dependsvec[0] = 0;
+
+       if (dependsstr != 0)
+       {
+               p = strdup(dependsstr);
+               while (*p != 0 && *p != '\n')
+               {
+                       if (*p != ' ')
+                       {
+                               if (*p == ',')
+                               {
+                                       *p = 0;
+                                       dependsvec[++i] = 0;
+                               }
+                               else if (dependsvec[i] == 0)
+                                       dependsvec[i] = p;
+                       }
+                       else
+                               *p = 0; /* eat the space... */
+                       p++;
+               }
+               *p = 0;
+       }
+       dependsvec[i+1] = 0;
+       return dependsvec;
+}
+
+static void depends_sort_visit(struct package_t **ordered, 
+       struct package_t *pkgs, struct package_t *pkg)
+{
+       /* Topological sort algorithm:
+        * ordered is the output list, pkgs is the dependency graph, pkg is 
+        * the current node
+        *
+        * recursively add all the adjacent nodes to the ordered list, marking
+        * each one as visited along the way
+        *
+        * yes, this algorithm looks a bit odd when all the params have the
+        * same type :-)
+        */
+       unsigned short i;
+
+       /* mark node as processing */
+       pkg->color = COLOR_GRAY;
+
+       /* visit each not-yet-visited node */
+       for (i = 0; i < pkg->requiredcount; i++)
+               if (pkg->requiredfor[i]->color == COLOR_WHITE)
+                       depends_sort_visit(ordered, pkgs, pkg->requiredfor[i]);
+
+#if 0
+       /* add it to the list */
+       newnode = (struct package_t *)malloc(sizeof(struct package_t));
+       /* make a shallow copy */
+       *newnode = *pkg;
+       newnode->next = *ordered;
+       *ordered = newnode;
+#endif
+       pkg->next = *ordered;
+       *ordered = pkg;
+
+       /* mark node as done */
+       pkg->color = COLOR_BLACK;
+}
+
+static struct package_t *depends_sort(struct package_t *pkgs)
+{
+       /* TODO: it needs to break cycles in the to-be-installed package 
+        * graph... */
+       struct package_t *ordered = NULL;
+       struct package_t *pkg;
+
+       for (pkg = pkgs; pkg != 0; pkg = pkg->next)
+               pkg->color = COLOR_WHITE;
+
+       for (pkg = pkgs; pkg != 0; pkg = pkg->next)
+               if (pkg->color == COLOR_WHITE)
+                       depends_sort_visit(&ordered, pkgs, pkg);
+
+       /* Leaks the old list... return the new one... */
+       return ordered;
+}
+
+
+/* resolve package dependencies -- 
+ * for each package in the list of packages to be installed, we parse its 
+ * dependency info to determine if the dependent packages are either 
+ * already installed, or are scheduled to be installed. If both tests fail
+ * than bail.
+ *
+ * The algorithm here is O(n^2*m) where n = number of packages to be 
+ * installed and m is the # of dependencies per package. Not a terribly
+ * efficient algorithm, but given that at any one time you are unlikely
+ * to install a very large number of packages it doesn't really matter
+ */
+struct package_t *depends_resolve(struct package_t *pkgs, void *status)
+{
+       struct package_t *pkg, *chk;
+       struct package_t dependpkg;
+       char **dependsvec;
+       int i;
+       void *found;
+
+       for (pkg = pkgs; pkg != 0; pkg = pkg->next)
+       {
+               dependsvec = depends_split(pkg->depends);
+               i = 0;
+               while (dependsvec[i] != 0)
+               {
+                       /* Check for dependencies; first look for installed packages */
+                       dependpkg.package = dependsvec[i];
+                       if ((found = tfind(&dependpkg, &status, package_compare)) == 0 ||
+                           ((chk = *(struct package_t **)found) &&
+                            (chk->status & (STATUS_FLAGOK | STATUS_STATUSINSTALLED)) != 
+                             (STATUS_FLAGOK | STATUS_STATUSINSTALLED)))
+                       {
+                               /* if it fails, we look through the list of packages we are going to 
+                                * install */
+                               for (chk = pkgs; chk != 0; chk = chk->next)
+                               {
+                                       if (strcmp(chk->package, dependsvec[i]) == 0 ||
+                                           (chk->provides && 
+                                            strncmp(chk->provides, dependsvec[i], strlen(dependsvec[i])) == 0))
+                                       {
+                                               if (chk->requiredcount >= DEPENDSMAX)
+                                               {
+                                                       fprintf(stderr, "Too many dependencies for %s\n", 
+                                                               chk->package);
+                                                       return 0;
+                                               }
+                                               if (chk != pkg)
+                                                       chk->requiredfor[chk->requiredcount++] = pkg;
+                                               break;
+                                       }
+                               }
+                               if (chk == 0)
+                               {
+                                       fprintf(stderr, "%s depends on %s, but it is not going to be installed\n", pkg->package, dependsvec[i]);
+                                       return 0;
+                               }
+                       }
+                       i++;
+               }
+       }
+
+       return depends_sort(pkgs);
+}
+#endif
+
+/* Status file handling routines
+ * 
+ * This is a fairly minimalistic implementation. there are two main functions 
+ * that are supported:
+ * 
+ * 1) reading the entire status file:
+ *    the status file is read into memory as a binary-tree, with just the 
+ *    package and status info preserved
+ *
+ * 2) merging the status file
+ *    control info from (new) packages is merged into the status file, 
+ *    replacing any pre-existing entries. when a merge happens, status info 
+ *    read using the status_read function is written back to the status file
+ */
+
+static const char *statuswords[][10] = {
+       { (char *)STATUS_WANTSTART, "unknown", "install", "hold", 
+               "deinstall", "purge", 0 },
+       { (char *)STATUS_FLAGSTART, "ok", "reinstreq", "hold", 
+               "hold-reinstreq", 0 },
+       { (char *)STATUS_STATUSSTART, "not-installed", "unpacked", "half-configured",
+               "installed", "half-installed",
+               "config-files", "post-inst-failed", 
+               "removal-failed", 0 }
+};
+
+int package_compare(const void *p1, const void *p2)
+{
+       return strcmp(((struct package_t *)p1)->package, 
+               ((struct package_t *)p2)->package);
+}
+
+static unsigned long status_parse(const char *line)
+{
+       char *p;
+       int i, j;
+       unsigned long l = 0;
+       for (i = 0; i < 3; i++)
+       {
+               p = strchr(line, ' ');
+               if (p) *p = 0; 
+               j = 1;
+               while (statuswords[i][j] != 0) 
+               {
+                       if (strcmp(line, statuswords[i][j]) == 0) 
+                       {
+                               l |= (1 << ((int)statuswords[i][0] + j - 1));
+                               break;
+                       }
+                       j++;
+               }
+               if (statuswords[i][j] == 0) return 0; /* parse error */
+               line = p+1;
+       }
+       return l;
+}
+
+static const char *status_print(unsigned long flags)
+{
+       /* this function returns a static buffer... */
+       static char buf[256];
+       int i, j;
+
+       buf[0] = 0;
+       for (i = 0; i < 3; i++)
+       {
+               j = 1;
+               while (statuswords[i][j] != 0)
+               {
+                       if ((flags & (1 << ((int)statuswords[i][0] + j - 1))) != 0)
+                       {
+                               strcat(buf, statuswords[i][j]);
+                               if (i < 2) strcat(buf, " ");
+                               break;
+                       }
+                       j++;
+               }
+               if (statuswords[i][j] == 0)
+               {
+                       fprintf(stderr, "corrupted status flag!!\n");
+                       return NULL;
+               }
+       }
+       return buf;
+}
+
+/*
+ * Read a control file (or a stanza of a status file) and parse it,
+ * filling parsed fields into the package structure
+ */
+void control_read(FILE *f, struct package_t *p)
+{
+       char buf[BUFSIZE];
+       while (fgets(buf, BUFSIZE, f) && !feof(f))
+       {
+               buf[strlen(buf)-1] = 0;
+               if (*buf == 0)
+                       return;
+               else if (strstr(buf, "Package: ") == buf)
+               {
+                       p->package = strdup(buf+9);
+               }
+               else if (strstr(buf, "Status: ") == buf)
+               {
+                       p->status = status_parse(buf+8);
+               }
+               else if (strstr(buf, "Depends: ") == buf)
+               {
+                       p->depends = strdup(buf+9);
+               }
+               else if (strstr(buf, "Provides: ") == buf)
+               {
+                       p->provides = strdup(buf+10);
+               }
+               /* This is specific to the Debian Installer. Ifdef? */
+               else if (strstr(buf, "installer-menu-item: ") == buf) 
+               {
+                       p->installer_menu_item = atoi(buf+21);
+               }
+               else if (strstr(buf, "Description: ") == buf)
+               {
+                       p->description = strdup(buf+13);
+               }
+               /* TODO: localized descriptions */
+       }
+}
+
+void *status_read(void)
+{
+       FILE *f;
+       void *status = 0;
+       struct package_t *m = 0, *p = 0, *t = 0;
+
+       if ((f = fopen(STATUSFILE, "r")) == NULL)
+       {
+               perror(STATUSFILE);
+               return 0;
+       }
+       if (getenv(UDPKG_QUIET) == NULL)
+               printf("(Reading database...)\n");
+       while (!feof(f))
+       {
+               m = (struct package_t *)malloc(sizeof(struct package_t));
+               memset(m, 0, sizeof(struct package_t));
+               control_read(f, m);
+               if (m->package)
+               {
+                       /*
+                        * If there is an item in the tree by this name,
+                        * it must be a virtual package; insert real
+                        * package in preference.
+                        */
+                       tdelete(m, &status, package_compare);
+                       tsearch(m, &status, package_compare);
+                       if (m->provides)
+                       {
+                               /* 
+                                * A "Provides" triggers the insertion
+                                * of a pseudo package into the status
+                                * binary-tree.
+                                */
+                               p = (struct package_t *)malloc(sizeof(struct package_t));
+                               memset(p, 0, sizeof(struct package_t));
+                               p->package = strdup(m->provides);
+
+                               t = *(struct package_t **)tsearch(p, &status, package_compare);
+                               if (!(t == p))
+                               {
+                                       free(p->package);
+                                       free(p);
+                               }
+                               else {
+                                       /*
+                                        * Pseudo package status is the
+                                        * same as the status of the
+                                        * package providing it 
+                                        * FIXME: (not quite right, if 2
+                                        * packages of different statuses
+                                        * provide it).
+                                        */
+                                       t->status = m->status;
+                               }
+                       }
+               }
+               else
+               {
+                       free(m);
+               }
+       }
+       fclose(f);
+       return status;
+}
+
+int status_merge(void *status, struct package_t *pkgs)
+{
+       FILE *fin, *fout;
+       char buf[BUFSIZE];
+       struct package_t *pkg = 0, *statpkg = 0;
+       struct package_t locpkg;
+       int r = 0;
+
+       if ((fin = fopen(STATUSFILE, "r")) == NULL)
+       {
+               perror(STATUSFILE);
+               return 0;
+       }
+       if ((fout = fopen(STATUSFILE ".new", "w")) == NULL)
+       {
+               perror(STATUSFILE ".new");
+               return 0;
+       }
+       if (getenv(UDPKG_QUIET) == NULL)
+               printf("(Updating database...)\n");
+       while (fgets(buf, BUFSIZE, fin) && !feof(fin))
+       {
+               buf[strlen(buf)-1] = 0; /* trim newline */
+               /* If we see a package header, find out if it's a package
+                * that we have processed. if so, we skip that block for
+                * now (write it at the end).
+                *
+                * we also look at packages in the status cache and update
+                * their status fields
+                */
+               if (strstr(buf, "Package: ") == buf)
+               {
+                       for (pkg = pkgs; pkg != 0 && strncmp(buf+9,
+                                       pkg->package, strlen(pkg->package))!=0;
+                            pkg = pkg->next) ;
+
+                       locpkg.package = buf+9;
+                       statpkg = tfind(&locpkg, &status, package_compare);
+                       
+                       /* note: statpkg should be non-zero, unless the status
+                        * file was changed while we are processing (no locking
+                        * is currently done...
+                        */
+                       if (statpkg != 0) statpkg = *(struct package_t **)statpkg;
+               }
+               if (pkg != 0) continue;
+
+               if (strstr(buf, "Status: ") == buf && statpkg != 0)
+               {
+                         snprintf(buf, sizeof(buf), "Status: %s",
+                                status_print(statpkg->status));
+               }
+               fputs(buf, fout);
+               fputc('\n', fout);
+       }
+
+       // Print out packages we processed.
+       for (pkg = pkgs; pkg != 0; pkg = pkg->next) {
+               fprintf(fout, "Package: %s\nStatus: %s\n", 
+                       pkg->package, status_print(pkg->status));
+               if (pkg->depends)
+                       fprintf(fout, "Depends: %s\n", pkg->depends);
+               if (pkg->provides)
+                       fprintf(fout, "Provides: %s\n", pkg->provides);
+               if (pkg->installer_menu_item)
+                       fprintf(fout, "installer-menu-item: %i\n", pkg->installer_menu_item);
+               if (pkg->description)
+                       fprintf(fout, "Description: %s\n", pkg->description);
+               fputc('\n', fout);
+       }
+       
+       fclose(fin);
+       fclose(fout);
+
+       r = rename(STATUSFILE, STATUSFILE ".bak");
+       if (r == 0) r = rename(STATUSFILE ".new", STATUSFILE);
+       return 0;
+}
+
+#include <errno.h>
+#include <fcntl.h>
+#include <search.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <utime.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+
+/* 
+ * Main udpkg implementation routines
+ */
+
+#ifdef DODEBUG
+static int do_system(const char *cmd)
+{
+       DPRINTF("cmd is %s\n", cmd);
+       return system(cmd);
+}
+#else
+#define do_system(cmd) system(cmd)
+#endif
+
+static int is_file(const char *fn)
+{
+       struct stat statbuf;
+
+       if (stat(fn, &statbuf) < 0) return 0;
+       return S_ISREG(statbuf.st_mode);
+}
+
+static int dpkg_copyfile(const char *src, const char *dest)
+{
+       /* copy a (regular) file if it exists, preserving the mode, mtime 
+        * and atime */
+       char buf[8192];
+       int infd, outfd;
+       int r;
+       struct stat srcStat;
+       struct utimbuf times;
+
+       if (stat(src, &srcStat) < 0) 
+       {
+               if (errno == 2) return 0; else return -1;
+       }
+       if ((infd = open(src, O_RDONLY)) < 0) 
+               return -1;
+       if ((outfd = open(dest, O_WRONLY|O_CREAT|O_TRUNC, srcStat.st_mode)) < 0)
+               return -1;
+       while ((r = read(infd, buf, sizeof(buf))) > 0)
+       {
+               if (write(outfd, buf, r) < 0)
+                       return -1;
+       }
+       close(outfd);
+       close(infd);
+       if (r < 0) return -1;
+       times.actime = srcStat.st_atime;
+       times.modtime = srcStat.st_mtime;
+       if (utime(dest, &times) < 0) return -1;
+       return 1;
+}
+
+static int dpkg_doconfigure(struct package_t *pkg)
+{
+       int r;
+       char postinst[1024];
+       char buf[1024];
+       DPRINTF("Configuring %s\n", pkg->package);
+       pkg->status &= STATUS_STATUSMASK;
+       snprintf(postinst, sizeof(postinst), "%s%s.postinst", INFODIR, pkg->package);
+       if (is_file(postinst))
+       {
+               snprintf(buf, sizeof(buf), "%s configure", postinst);
+               if ((r = do_system(buf)) != 0)
+               {
+                       fprintf(stderr, "postinst exited with status %d\n", r);
+                       pkg->status |= STATUS_STATUSHALFCONFIGURED;
+                       return 1;
+               }
+       }
+
+       pkg->status |= STATUS_STATUSINSTALLED;
+       
+       return 0;
+}
+
+static int dpkg_dounpack(struct package_t *pkg)
+{
+       int r = 0;
+       char *cwd, *p;
+       FILE *infp, *outfp;
+       char buf[1024], buf2[1024];
+       int i;
+       char *adminscripts[] = { "prerm", "postrm", "preinst", "postinst",
+                                "conffiles", "md5sums", "shlibs", 
+                                "templates" };
+
+       DPRINTF("Unpacking %s\n", pkg->package);
+
+       cwd = getcwd(0, 0);
+       chdir("/");
+       snprintf(buf, sizeof(buf), "ar -p %s data.tar.gz|zcat|tar -xf -", pkg->file);
+       if (SYSTEM(buf) == 0)
+       {
+               /* Installs the package scripts into the info directory */
+               for (i = 0; i < sizeof(adminscripts) / sizeof(adminscripts[0]);
+                    i++)
+               {
+                       snprintf(buf, sizeof(buf), "%s%s/%s",
+                               DPKGCIDIR, pkg->package, adminscripts[i]);
+                       snprintf(buf2, sizeof(buf), "%s%s.%s", 
+                               INFODIR, pkg->package, adminscripts[i]);
+                       if (dpkg_copyfile(buf, buf2) < 0)
+                       {
+                               fprintf(stderr, "Cannot copy %s to %s: %s\n", 
+                                       buf, buf2, strerror(errno));
+                               r = 1;
+                               break;
+                       }
+                       else
+                       {
+                               /* ugly hack to create the list file; should
+                                * probably do something more elegant
+                                *
+                                * why oh why does dpkg create the list file
+                                * so oddly...
+                                */
+                               snprintf(buf, sizeof(buf), 
+                                       "ar -p %s data.tar.gz|zcat|tar -tf -", 
+                                       pkg->file);
+                               snprintf(buf2, sizeof(buf2),
+                                       "%s%s.list", INFODIR, pkg->package);
+                               if ((infp = popen(buf, "r")) == NULL ||
+                                   (outfp = fopen(buf2, "w")) == NULL)
+                               {
+                                       fprintf(stderr, "Cannot create %s\n",
+                                               buf2);
+                                       r = 1;
+                                       break;
+                               }
+                               while (fgets(buf, sizeof(buf), infp) &&
+                                      !feof(infp))
+                               {
+                                       p = buf;
+                                       if (*p == '.') p++;
+                                       if (*p == '/' && *(p+1) == '\n')
+                                       {
+                                               *(p+1) = '.';
+                                               *(p+2) = '\n';
+                                               *(p+3) = 0;
+                                       }
+                                       if (p[strlen(p)-2] == '/')
+                                       {
+                                               p[strlen(p)-2] = '\n';
+                                               p[strlen(p)-1] = 0;
+                                       }
+                                       fputs(p, outfp);
+                               }
+                               fclose(infp);
+                               fclose(outfp);
+                       }
+               }
+               pkg->status &= STATUS_WANTMASK;
+               pkg->status |= STATUS_WANTINSTALL;
+               pkg->status &= STATUS_FLAGMASK;
+               pkg->status |= STATUS_FLAGOK;
+               pkg->status &= STATUS_STATUSMASK;
+               if (r == 0)
+                       pkg->status |= STATUS_STATUSUNPACKED;
+               else
+                       pkg->status |= STATUS_STATUSHALFINSTALLED;
+       }
+       chdir(cwd);
+       return r;
+}
+
+static int dpkg_doinstall(struct package_t *pkg)
+{
+       DPRINTF("Installing %s\n", pkg->package);
+       return (dpkg_dounpack(pkg) || dpkg_doconfigure(pkg));
+}
+
+static int dpkg_unpackcontrol(struct package_t *pkg)
+{
+       int r = 1;
+       char *cwd = 0;
+       char *p;
+       char buf[1024];
+       FILE *f;
+
+       p = strrchr(pkg->file, '/');
+       if (p) p++; else p = pkg->file;
+       p = pkg->package = strdup(p);
+       while (*p != 0 && *p != '_' && *p != '.') p++;
+       *p = 0;
+
+       cwd = getcwd(0, 0);
+       snprintf(buf, sizeof(buf), "%s%s", DPKGCIDIR, pkg->package);
+       DPRINTF("dir = %s\n", buf);
+       if (mkdir(buf, S_IRWXU) == 0 && chdir(buf) == 0)
+       {
+               snprintf(buf, sizeof(buf), "ar -p %s control.tar.gz|zcat|tar -xf -",
+                       pkg->file);
+               if (SYSTEM(buf) == 0)
+               {
+                       if ((f = fopen("control", "r")) != NULL) {
+                               control_read(f, pkg);
+                               r = 0;
+                       }
+               }
+       }
+
+       chdir(cwd);
+       free(cwd);
+       return r;
+}
+
+static int dpkg_unpack(struct package_t *pkgs)
+{
+       int r = 0;
+       struct package_t *pkg;
+       void *status = status_read();
+
+       if (SYSTEM("rm -rf -- " DPKGCIDIR) != 0 ||
+           mkdir(DPKGCIDIR, S_IRWXU) != 0)
+       {
+               perror("mkdir");
+               return 1;
+       }
+       
+       for (pkg = pkgs; pkg != 0; pkg = pkg->next)
+       {
+               dpkg_unpackcontrol(pkg);
+               r = dpkg_dounpack(pkg);
+               if (r != 0) break;
+       }
+       status_merge(status, pkgs);
+       SYSTEM("rm -rf -- " DPKGCIDIR);
+       return r;
+}
+
+static int dpkg_configure(struct package_t *pkgs)
+{
+       int r = 0;
+       void *found;
+       struct package_t *pkg;
+       void *status = status_read();
+       for (pkg = pkgs; pkg != 0 && r == 0; pkg = pkg->next)
+       {
+               found = tfind(pkg, &status, package_compare);
+               if (found == 0)
+               {
+                       fprintf(stderr, "Trying to configure %s, but it is not installed\n", pkg->package);
+                       r = 1;
+               }
+               else
+               {
+                       /* configure the package listed in the status file;
+                        * not pkg, as we have info only for the latter */
+                       r = dpkg_doconfigure(*(struct package_t **)found);
+               }
+       }
+       status_merge(status, 0);
+       return r;
+}
+
+static int dpkg_install(struct package_t *pkgs)
+{
+       struct package_t *p, *ordered = 0;
+       void *status = status_read();
+       if (SYSTEM("rm -rf -- " DPKGCIDIR) != 0 ||
+           mkdir(DPKGCIDIR, S_IRWXU) != 0)
+       {
+               perror("mkdir");
+               return 1;
+       }
+       
+       /* Stage 1: parse all the control information */
+       for (p = pkgs; p != 0; p = p->next)
+               if (dpkg_unpackcontrol(p) != 0)
+               {
+                       perror(p->file);
+                       /* force loop break, and prevents further ops */
+                       pkgs = 0;
+               }
+       
+       /* Stage 2: resolve dependencies */
+#ifdef DODEPENDS
+       ordered = depends_resolve(pkgs, status);
+#else
+       ordered = pkgs;
+#endif
+       
+       /* Stage 3: install */
+       for (p = ordered; p != 0; p = p->next)
+       {
+               p->status &= STATUS_WANTMASK;
+               p->status |= STATUS_WANTINSTALL;
+
+               /* for now the flag is always set to ok... this is probably
+                * not what we want
+                */
+               p->status &= STATUS_FLAGMASK;
+               p->status |= STATUS_FLAGOK;
+
+               if (dpkg_doinstall(p) != 0)
+               {
+                       perror(p->file);
+               }
+       }
+       
+       if (ordered != 0)
+               status_merge(status, pkgs);
+       SYSTEM("rm -rf -- " DPKGCIDIR);
+       return 0;
+}
+
+static int dpkg_remove(struct package_t *pkgs)
+{
+       struct package_t *p;
+       void *status = status_read();
+       for (p = pkgs; p != 0; p = p->next)
+       {
+       }
+       status_merge(status, 0);
+       return 0;
+}
+
+int dpkg_main(int argc, char **argv)
+{
+       char opt = 0;
+       char *s;
+       struct package_t *p, *packages = NULL;
+       char *cwd = getcwd(0, 0);
+       while (*++argv)
+       {
+               if (**argv == '-') {
+                       /* Nasty little hack to "parse" long options. */
+                       s = *argv;
+                       while (*s == '-')
+                               s++;
+                       opt=s[0];
+               }
+               else
+               {
+                       p = (struct package_t *)malloc(sizeof(struct package_t));
+                       memset(p, 0, sizeof(struct package_t));
+                       if (**argv == '/')
+                               p->file = *argv;
+                       else if (opt != 'c')
+                       {
+                               p->file = malloc(strlen(cwd) + strlen(*argv) + 2);
+                               sprintf(p->file, "%s/%s", cwd, *argv);
+                       }
+                       else {
+                               p->package = strdup(*argv);
+                       }
+                       p->next = packages;
+                       packages = p;
+               }
+                       
+       }
+       switch (opt)
+       {
+               case 'i': return dpkg_install(packages); break;
+               case 'r': return dpkg_remove(packages); break;
+               case 'u': return dpkg_unpack(packages); break;
+               case 'c': return dpkg_configure(packages); break;
+       }
+
+       /* if it falls through to here, some of the command line options were
+          wrong */
+       usage(dpkg_usage);
+       return 0;
+}
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