From 14d4c3fe7e351c12f1cc4ec6246a23ae94dca7da Mon Sep 17 00:00:00 2001
From: José Bollo <jose.bollo@iot.bzh>
Date: Thu, 2 Mar 2017 14:59:52 +0100
Subject: improves matching of patterns for unit description
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
Change-Id: I2c3f9f0b45b79d5baa9ad5c19876f1412456c19d
Signed-off-by: José Bollo <jose.bollo@iot.bzh>
---
src/wgtpkg-unit.c | 219 ++++++++++++++++++++++++++++++++++++++----------------
1 file changed, 156 insertions(+), 63 deletions(-)
diff --git a/src/wgtpkg-unit.c b/src/wgtpkg-unit.c
index 8569c5a..26cf324 100644
--- a/src/wgtpkg-unit.c
+++ b/src/wgtpkg-unit.c
@@ -25,15 +25,69 @@
#include <unistd.h>
#include <string.h>
#include <errno.h>
-
+
#include "verbose.h"
#include "utils-file.h"
#include "wgtpkg-mustach.h"
#include "wgtpkg-unit.h"
+#if 0
+#include <ctype.h>
+#else
+#define isblank(c) ((c)==' '||(c)=='\t')
+#endif
+
+/* the template for all units */
static char *template;
+/*
+ * Search for the 'pattern' in 'text'.
+ * Returns 1 if 'text' matches the 'pattern' or else returns 0.
+ * When returning 1 and 'after' isn't NULL, the pointer to the
+ * first character after the pettern in 'text' is stored in 'after'.
+ * The characters '\n' and ' ' have a special mening in the search:
+ * * '\n': matches any space or tabs (including none) followed
+ * either by '\n' or '\0' (end of the string)
+ * * ' ': matches any space or tabs but at least one.
+ */
+static int matches(const char *pattern, char *text, char **after)
+{
+ char p, t;
+
+ t = *text;
+ p = *pattern;
+ while(p) {
+ switch(p) {
+ case '\n':
+ while (isblank(t))
+ t = *++text;
+ if (t) {
+ if (t != p)
+ return 0;
+ t = *++text;
+ }
+ break;
+ case ' ':
+ if (!isblank(t))
+ return 0;
+ do {
+ t = *++text;
+ } while(isblank(t));
+ break;
+ default:
+ if (t != p)
+ return 0;
+ t = *++text;
+ break;
+ }
+ p = *++pattern;
+ }
+ if (after)
+ *after = text;
+ return 1;
+}
+
/*
* Pack a null terminated 'text' by removing empty lines,
* lines made of blanks and terminated with \, lines
@@ -42,20 +96,30 @@ static char *template;
* "nl" exactly (without quotes ") are replaced with
* an empty line.
*
- * Returns the pointer to the ending null.
+ * Returns the size after packing (offset of the ending null).
*/
-static char *pack(char *text, char purge)
+static size_t pack(char *text, char purge)
{
- char *read, *write, *begin, *start, c, emit, cont, nextcont;
+ char *read; /* read iterator */
+ char *write; /* write iterator */
+ char *begin; /* begin the copied text of the line */
+ char *start; /* first character of the line that isn't blanck */
+ char c; /* currently scanned character (pointed by read) */
+ char emit; /* flag telling whether line is to be copied */
+ char cont; /* flag telling whether the line continues the previous one */
+ char nextcont; /* flag telling whether the line will continues the next one */
cont = 0;
- c = *(begin = write = read = text);
+ c = *(write = read = text);
+
+ /* iteration over lines */
while (c) {
+ /* computes emit, nextcont, emit and start for the current line */
emit = nextcont = 0;
start = NULL;
begin = read;
while (c && c != '\n') {
- if (c != ' ' && c != '\t') {
+ if (!isblank(c)) {
if (c == '\\' && read[1] == '\n')
nextcont = 1;
else {
@@ -68,13 +132,18 @@ static char *pack(char *text, char purge)
}
if (c)
c = *++read;
+ /* emit the line if not empty */
if (emit) {
+ /* removes the blanks on the left of not continuing lines */
if (!cont && start)
begin = start;
+ /* check if purge applies */
if (purge && *begin == purge) {
+ /* yes, insert new line if requested */
if (!strncmp(begin+1, "nl\n",3))
*write++ = '\n';
} else {
+ /* copies the line */
while (begin != read)
*write++ = *begin++;
}
@@ -82,7 +151,7 @@ static char *pack(char *text, char purge)
cont = nextcont;
}
*write = 0;
- return write;
+ return (size_t)(write - text);
}
/*
@@ -104,54 +173,45 @@ static inline char *nextline(char *text)
*/
static char *offset(char *text, const char *pattern, char **args)
{
- size_t len;
-
- if (text) {
- len = strlen(pattern);
- do {
- if (strncmp(text, pattern, len))
- text = nextline(text);
- else {
- if (args)
- *args = &text[len];
- break;
- }
- } while (text);
- }
+ while (text && !matches(pattern, text, args))
+ text = nextline(text);
return text;
}
/*
* process one unit
*/
-
static int process_one_unit(char *spec, struct unitdesc *desc)
{
- char *nsoc, *nsrv;
+ char *nsoc, *nsrv, *name;
int isuser, issystem, issock, isserv;
+ size_t len;
- /* found the configuration directive of the unit */
+ /* finds the configuration directive of the unit */
isuser = !!offset(spec, "%systemd-unit user\n", NULL);
issystem = !!offset(spec, "%systemd-unit system\n", NULL);
issock = !!offset(spec, "%systemd-unit socket ", &nsoc);
isserv = !!offset(spec, "%systemd-unit service ", &nsrv);
- if (isuser ^ issystem) {
+ /* check the unit scope */
+ if ((isuser + issystem) == 1) {
desc->scope = isuser ? unitscope_user : unitscope_system;
} else {
desc->scope = unitscope_unknown;
}
- if (issock ^ isserv) {
+ /* check the unit type */
+ if ((issock + isserv) == 1) {
if (issock) {
desc->type = unittype_socket;
- desc->name = nsoc;
+ name = nsoc;
} else {
desc->type = unittype_service;
- desc->name = nsrv;
+ name = nsrv;
}
- desc->name_length = (size_t)(strchrnul(desc->name, '\n') - desc->name);
- desc->name = strndup(desc->name, desc->name_length);
+ len = (size_t)(strchrnul(name, '\n') - name);
+ desc->name = strndup(name, len);
+ desc->name_length = desc->name ? len : 0;
} else {
desc->type = unittype_unknown;
desc->name = NULL;
@@ -159,52 +219,69 @@ static int process_one_unit(char *spec, struct unitdesc *desc)
}
desc->content = spec;
- desc->content_length = (size_t)(pack(spec, '%') - spec);
+ desc->content_length = pack(spec, '%');
return 0;
}
/*
+ * Processes all the units of the 'corpus'.
+ * Each unit of the corpus is separated and packed and its
+ * charactistics are stored in a descriptor.
+ * At the end if no error was found, calls the function 'process'
+ * with its given 'closure' and the array descripbing the units.
+ * Return 0 in case of success or a negative value in case of error.
*/
-static int process_all_units(char *spec, int (*process)(void *closure, const struct unitdesc descs[], unsigned count), void *closure)
+static int process_all_units(char *corpus, int (*process)(void *closure, const struct unitdesc descs[], unsigned count), void *closure)
{
int rc, rc2;
unsigned n;
- char *beg, *end, *after;
+ char *beg, *end;
struct unitdesc *descs, *d;
descs = NULL;
n = 0;
- rc = 0;
- beg = offset(spec, "%begin systemd-unit\n", NULL);
- while(beg) {
- beg = nextline(beg);
- end = offset(beg, "%end systemd-unit\n", &after);
+ rc = rc2 = 0;
+
+ /* while there is a unit in the corpus */
+ while(offset(corpus, "%begin systemd-unit\n", &beg)) {
+
+ /* get the end of the unit */
+ end = offset(beg, "%end systemd-unit\n", &corpus);
if (!end) {
/* unterminated unit !! */
ERROR("unterminated unit description!! %s", beg);
- break;
+ corpus = beg;
+ rc2 = -EINVAL;
+ } else {
+ /* separate the unit from the corpus */
+ *end = 0;
+
+ /* allocates a descriptor for the unit */
+ d = realloc(descs, (n + 1) * sizeof *descs);
+ if (d == NULL)
+ rc2 = -ENOMEM;
+ else {
+ /* creates the unit description */
+ memset(&d[n], 0, sizeof *d);
+ descs = d;
+ rc2 = process_one_unit(beg, &descs[n]);
+ if (rc2 >= 0)
+ n++;
+ }
}
- *end = 0;
-
- d = realloc(descs, (n + 1) * sizeof *descs);
- if (d == NULL)
- rc2 = -ENOMEM;
- else {
- memset(&d[n], 0, sizeof *d);
- descs = d;
- rc2 = process_one_unit(beg, &descs[n]);
+ /* records the error if there is an error */
+ if (rc2 < 0) {
+ rc = rc ? : rc2;
+ rc2 = 0;
}
-
- if (rc2 >= 0)
- n++;
- else if (rc == 0)
- rc = rc2;
- beg = offset(after, "%begin systemd-unit\n", NULL);
}
+ /* call the function that processes the units */
if (rc == 0 && process)
rc = process(closure, descs, n);
+
+ /* cleanup and frees */
while(n)
free((char *)(descs[--n].name));
free(descs);
@@ -212,15 +289,29 @@ static int process_all_units(char *spec, int (*process)(void *closure, const str
return rc;
}
+/*
+ * Clear the unit generator
+ */
+void unit_generator_off()
+{
+ free(template);
+ template = NULL;
+}
+
+/*
+ * Initialises the unit generator with 'filename'.
+ * Returns 0 in case of success or a negative number in case of error.
+ */
int unit_generator_on(const char *filename)
{
size_t size;
char *tmp;
int rc;
+ unit_generator_off();
rc = getfile(filename ? : FWK_UNIT_CONF, &template, NULL);
if (!rc) {
- size = (size_t)(pack(template, ';') - template);
+ size = pack(template, ';');
tmp = realloc(template, 1 + size);
if (tmp)
template = tmp;
@@ -228,12 +319,15 @@ int unit_generator_on(const char *filename)
return rc;
}
-void unit_generator_off()
-{
- free(template);
- template = NULL;
-}
-
+/*
+ * Applies the object 'jdesc' to the current unit generator.
+ * The current unit generator will be set to the default one if not unit
+ * was previously set using the function 'unit_generator_on'.
+ * The callback function 'process' is then called with the
+ * unit descriptors array and the expected closure.
+ * Return what returned process in case of success or a negative
+ * error code.
+ */
int unit_generator_process(struct json_object *jdesc, int (*process)(void *closure, const struct unitdesc descs[], unsigned count), void *closure)
{
int rc;
@@ -244,9 +338,8 @@ int unit_generator_process(struct json_object *jdesc, int (*process)(void *closu
if (!rc) {
instance = NULL;
rc = apply_mustach(template, jdesc, &instance, &size);
- if (!rc) {
+ if (!rc)
rc = process_all_units(instance, process, closure);
- }
free(instance);
}
return rc;
--
cgit