[pacman-dev] [PATCH] Add a fetch callback to allow front-end download support
Sebastian Nowicki
sebnow at gmail.com
Fri Feb 20 02:21:56 EST 2009
This allows a frontend to define its own download algorithm so that the
libfetch dependency can be omitted without using an external process. The
callback will be used if it is defined, otherwise the internal method
(libfetch) is used, if available.
The external download method was moved to pacman and is set as the fetch
callback, if the command is defined in the configuration file.
Signed-off-by: Sebastian Nowicki <sebnow at gmail.com>
---
lib/libalpm/alpm.h | 14 +++++++
lib/libalpm/dload.c | 101 +------------------------------------------------
lib/libalpm/handle.c | 18 +++++++++
lib/libalpm/handle.h | 1 +
src/pacman/conf.h | 6 +++
src/pacman/pacman.c | 96 +++++++++++++++++++++++++++++++++++++++++++++++-
6 files changed, 137 insertions(+), 99 deletions(-)
diff --git a/lib/libalpm/alpm.h b/lib/libalpm/alpm.h
index 7b7ca4e..266f7ff 100644
--- a/lib/libalpm/alpm.h
+++ b/lib/libalpm/alpm.h
@@ -83,6 +83,17 @@ int alpm_logaction(char *fmt, ...);
typedef void (*alpm_cb_download)(const char *filename,
off_t xfered, off_t total);
typedef void (*alpm_cb_totaldl)(off_t total);
+/** A callback for downloading files
+ * @param url the URL of the file to be downloaded
+ * @param localpath the directory to which the file should be downloaded
+ * @param mtimeold the modification time of the file previously downloaded
+ * @param mtimenew the modification time of the newly downloaded file.
+ * This should be set by the callback.
+ * @return 0 on success, 1 if the modification times are identical, -1 on
+ * error.
+ */
+typedef int (*alpm_cb_fetch)(const char *url, const char *localpath,
+ time_t mtimeold, time_t *mtimenew);
/*
* Options
@@ -94,6 +105,9 @@ void alpm_option_set_logcb(alpm_cb_log cb);
alpm_cb_download alpm_option_get_dlcb();
void alpm_option_set_dlcb(alpm_cb_download cb);
+alpm_cb_fetch alpm_option_get_fetchcb();
+void alpm_option_set_fetchcb(alpm_cb_fetch cb);
+
alpm_cb_totaldl alpm_option_get_totaldlcb();
void alpm_option_set_totaldlcb(alpm_cb_totaldl cb);
diff --git a/lib/libalpm/dload.c b/lib/libalpm/dload.c
index 5b0a691..bc36706 100644
--- a/lib/libalpm/dload.c
+++ b/lib/libalpm/dload.c
@@ -262,111 +262,16 @@ cleanup:
}
#endif
-static int download_external(const char *url, const char *localpath,
- time_t mtimeold, time_t *mtimenew) {
- int ret = 0;
- int retval;
- int usepart = 0;
- char *ptr1, *ptr2;
- char origCmd[PATH_MAX];
- char parsedCmd[PATH_MAX] = "";
- char cwd[PATH_MAX];
- char *destfile, *tempfile, *filename;
-
- if(!handle->xfercommand) {
- RET_ERR(PM_ERR_EXTERNAL_DOWNLOAD, -1);
- }
-
- filename = get_filename(url);
- if(!filename) {
- RET_ERR(PM_ERR_EXTERNAL_DOWNLOAD, -1);
- }
- destfile = get_destfile(localpath, filename);
- tempfile = get_tempfile(localpath, filename);
-
- /* replace all occurrences of %o with fn.part */
- strncpy(origCmd, handle->xfercommand, sizeof(origCmd));
- ptr1 = origCmd;
- while((ptr2 = strstr(ptr1, "%o"))) {
- usepart = 1;
- ptr2[0] = '\0';
- strcat(parsedCmd, ptr1);
- strcat(parsedCmd, tempfile);
- ptr1 = ptr2 + 2;
- }
- strcat(parsedCmd, ptr1);
- /* replace all occurrences of %u with the download URL */
- strncpy(origCmd, parsedCmd, sizeof(origCmd));
- parsedCmd[0] = '\0';
- ptr1 = origCmd;
- while((ptr2 = strstr(ptr1, "%u"))) {
- ptr2[0] = '\0';
- strcat(parsedCmd, ptr1);
- strcat(parsedCmd, url);
- ptr1 = ptr2 + 2;
- }
- strcat(parsedCmd, ptr1);
- /* cwd to the download directory */
- getcwd(cwd, PATH_MAX);
- if(chdir(localpath)) {
- _alpm_log(PM_LOG_WARNING, _("could not chdir to %s\n"), localpath);
- pm_errno = PM_ERR_EXTERNAL_DOWNLOAD;
- ret = -1;
- goto cleanup;
- }
- /* execute the parsed command via /bin/sh -c */
- _alpm_log(PM_LOG_DEBUG, "running command: %s\n", parsedCmd);
- retval = system(parsedCmd);
-
- if(retval == -1) {
- _alpm_log(PM_LOG_WARNING, _("running XferCommand: fork failed!\n"));
- pm_errno = PM_ERR_EXTERNAL_DOWNLOAD;
- ret = -1;
- } else if(retval != 0) {
- /* download failed */
- _alpm_log(PM_LOG_DEBUG, "XferCommand command returned non-zero status "
- "code (%d)\n", retval);
- ret = -1;
- } else {
- /* download was successful */
- if(usepart) {
- rename(tempfile, destfile);
- }
- ret = 0;
- }
-
-cleanup:
- chdir(cwd);
- if(ret == -1) {
- /* hack to let an user the time to cancel a download */
- sleep(2);
- }
- FREE(destfile);
- FREE(tempfile);
-
- return(ret);
-}
-
static int download(const char *url, const char *localpath,
time_t mtimeold, time_t *mtimenew) {
- int ret;
-
- /* We have a few things to take into account here.
- * 1. If we have both internal/external available, choose based on
- * whether xfercommand is populated.
- * 2. If we only have external available, we should first check
- * if a command was provided before we drop into download_external.
- */
- if(handle->xfercommand == NULL) {
+ if(handle->fetchcb == NULL) {
#if defined(INTERNAL_DOWNLOAD)
- ret = download_internal(url, localpath, mtimeold, mtimenew);
+ handle->fetchcb = download_internal;
#else
RET_ERR(PM_ERR_EXTERNAL_DOWNLOAD, -1);
#endif
- } else {
- ret = download_external(url, localpath, mtimeold, mtimenew);
}
- return(ret);
+ return handle->fetchcb(url, localpath, mtimeold, mtimeold);
}
/*
diff --git a/lib/libalpm/handle.c b/lib/libalpm/handle.c
index 813f439..84e2c3f 100644
--- a/lib/libalpm/handle.c
+++ b/lib/libalpm/handle.c
@@ -105,6 +105,15 @@ alpm_cb_download SYMEXPORT alpm_option_get_dlcb()
return handle->dlcb;
}
+alpm_cb_fetch SYMEXPORT alpm_option_get_fetchcb()
+{
+ if (handle == NULL) {
+ pm_errno = PM_ERR_HANDLE_NULL;
+ return NULL;
+ }
+ return handle->fetchcb;
+}
+
alpm_cb_totaldl SYMEXPORT alpm_option_get_totaldlcb()
{
if (handle == NULL) {
@@ -258,6 +267,15 @@ void SYMEXPORT alpm_option_set_dlcb(alpm_cb_download cb)
handle->dlcb = cb;
}
+void SYMEXPORT alpm_option_set_fetchcb(alpm_cb_fetch cb)
+{
+ if (handle == NULL) {
+ pm_errno = PM_ERR_HANDLE_NULL;
+ return;
+ }
+ handle->fetchcb = cb;
+}
+
void SYMEXPORT alpm_option_set_totaldlcb(alpm_cb_totaldl cb)
{
if (handle == NULL) {
diff --git a/lib/libalpm/handle.h b/lib/libalpm/handle.h
index ad7666d..f895d85 100644
--- a/lib/libalpm/handle.h
+++ b/lib/libalpm/handle.h
@@ -40,6 +40,7 @@ typedef struct _pmhandle_t {
alpm_cb_log logcb; /* Log callback function */
alpm_cb_download dlcb; /* Download callback function */
alpm_cb_totaldl totaldlcb; /* Total download callback function */
+ alpm_cb_fetch fetchcb; /* Download file callback function */
/* filesystem paths */
char *root; /* Root path, default '/' */
diff --git a/src/pacman/conf.h b/src/pacman/conf.h
index 466d983..650b0f9 100644
--- a/src/pacman/conf.h
+++ b/src/pacman/conf.h
@@ -20,6 +20,11 @@
#define _PM_CONF_H
#include <alpm.h>
+#if defined(HAVE_SYS_SYSLIMITS_H)
+#include <sys/syslimits.h> /* PATH_MAX */
+#else
+#define PATH_MAX 1024
+#endif
typedef struct __config_t {
unsigned short op;
@@ -71,6 +76,7 @@ typedef struct __config_t {
unsigned short cleanmethod; /* select -Sc behavior */
alpm_list_t *holdpkg;
alpm_list_t *syncfirst;
+ char xfercommand[PATH_MAX]; /* external download command */
} config_t;
/* Operations */
diff --git a/src/pacman/pacman.c b/src/pacman/pacman.c
index 59916d6..0d6c897 100644
--- a/src/pacman/pacman.c
+++ b/src/pacman/pacman.c
@@ -573,6 +573,99 @@ static void setrepeatingoption(const char *ptr, const char *option,
pm_printf(PM_LOG_DEBUG, "config: %s: %s\n", option, p);
}
+/** External fetch callback */
+static int _download_with_xfercommand(const char *url, const char *localpath,
+ time_t mtimeold, time_t *mtimenew) {
+ int ret = 0;
+ int retval;
+ int usepart = 0;
+ char *ptr1, *ptr2;
+ char origCmd[PATH_MAX];
+ char parsedCmd[PATH_MAX] = "";
+ char cwd[PATH_MAX];
+ char *destfile, *tempfile, *filename;
+ int len;
+
+ if(!config->xfercommand) {
+ return -1;
+ }
+
+ filename = strrchr(url, '/');
+ if(!filename) {
+ return -1;
+ } else {
+ filename++; /* omit leading slash */
+ }
+
+ len = strlen(localpath) + strlen(filename) + 1;
+ destfile = calloc(len, sizeof(*destfile));
+ snprintf(destfile, len, "%s%s", localpath, filename);
+
+ len += 5; /* ".part" */
+ tempfile = calloc(len, sizeof(*tempfile));
+ snprintf(tempfile, len, "%s.part", destfile);
+
+ strncpy(origCmd, config->xfercommand, sizeof(origCmd));
+ /* replace all occurrences of %o with fn.part */
+ ptr1 = origCmd;
+ while((ptr2 = strstr(ptr1, "%o"))) {
+ usepart = 1;
+ ptr2[0] = '\0';
+ strcat(parsedCmd, ptr1);
+ strcat(parsedCmd, tempfile);
+ ptr1 = ptr2 + 2;
+ }
+ strcat(parsedCmd, ptr1);
+ /* replace all occurrences of %u with the download URL */
+ strncpy(origCmd, parsedCmd, sizeof(origCmd));
+ parsedCmd[0] = '\0';
+ ptr1 = origCmd;
+ while((ptr2 = strstr(ptr1, "%u"))) {
+ ptr2[0] = '\0';
+ strcat(parsedCmd, ptr1);
+ strcat(parsedCmd, url);
+ ptr1 = ptr2 + 2;
+ }
+ strcat(parsedCmd, ptr1);
+ /* cwd to the download directory */
+ getcwd(cwd, PATH_MAX);
+ if(chdir(localpath)) {
+ pm_printf(PM_LOG_DEBUG, "could not chdir to %s\n", localpath);
+ ret = -1;
+ goto cleanup;
+ }
+ /* execute the parsed command via /bin/sh -c */
+ pm_printf(PM_LOG_DEBUG, "running command: %s\n", parsedCmd);
+ retval = system(parsedCmd);
+
+ if(retval == -1) {
+ pm_printf(PM_LOG_DEBUG, "running XferCommand: fork failed!\n");
+ ret = -1;
+ } else if(retval != 0) {
+ /* download failed */
+ pm_printf(PM_LOG_DEBUG, "XferCommand command returned non-zero status "
+ "code (%d)\n", retval);
+ ret = -1;
+ } else {
+ /* download was successful */
+ if(usepart) {
+ rename(tempfile, destfile);
+ }
+ ret = 0;
+ }
+
+cleanup:
+ chdir(cwd);
+ if(ret == -1) {
+ /* hack to let an user the time to cancel a download */
+ sleep(2);
+ }
+ free(destfile);
+ free(tempfile);
+
+ return(ret);
+}
+
/* The real parseconfig. Called with a null section argument by the publicly
* visible parseconfig so we can recall from within ourself on an include */
static int _parseconfig(const char *file, const char *givensection,
@@ -736,7 +829,8 @@ static int _parseconfig(const char *file, const char *givensection,
pm_printf(PM_LOG_DEBUG, "config: logfile: %s\n", ptr);
}
} else if (strcmp(key, "XferCommand") == 0) {
- alpm_option_set_xfercommand(ptr);
+ strncpy(config->xfercommand, ptr, sizeof(config->xfercommand));
+ alpm_option_set_fetchcb(_download_with_xfercommand);
pm_printf(PM_LOG_DEBUG, "config: xfercommand: %s\n", ptr);
} else if (strcmp(key, "CleanMethod") == 0) {
if (strcmp(ptr, "KeepInstalled") == 0) {
--
1.6.1
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